import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.NoSuchElementException;


public class Main {
	public static void main(String[] args) {
		
		
		slover();
		out.flush();
	}
	static FastScanner sc = new FastScanner();
	static PrintWriter out = new PrintWriter(System.out);
	//StringBuffer S = new StringBuffer(sc.next());
	//String hoge2 = str.reverse().toString();
	//map.containsKey(A)
	//Map<Integer, Integer> map = new HashMap<Integer, Integer>(N);
	/*for ( キーのデータ型 key : マップの名前.keySet() ) {
		データのデータ型 data = マップの名前.get( key );
		
		// keyやdataを使った処理;
	}*/
	//int i = Integer.parseInt(s);
	//Queue<String> qq=new ArrayDeque<>(); //add,poll,peek BFSは前から実行される
	//Deque<String> dd=new ArrayDeque<>();//push後ろに入れる,poll(pop)後ろからとる,peek addは先頭に入るからバグ注意 
	//stackdfsは後ろから実行される
	//ArrayList<Integer> cc = new ArrayList<>(N);
	//cc.contains(tmp)
	//Arrays.asList(c).contains("a")
	//list.set(1,"walk");//1 1 2 3 5

	

	static int INF=(int) (Math.pow(10, 9)+7);
	
	private static int slover() {
		int N=sc.nextInt();
		
		int p[]=sc.nextIntArray(N, false);
		
		int v[]=p.clone();
		
		Arrays.parallelSort(v);
		int t=0;
		for(int i=0;i<N;i++) {
			
			if(p[i]!=v[i])t++;
			
			
		}
		//p(t);
		p(t==2||t==0 ? "YES":"NO");
		
		return 0;
		
		
	}
	
	
	
	
	
	
	static long Nsin(long t) {
		long sum=0;
		long v=1;
		long tt=1;
		for(long k=0;k<(t+"").length();k++) {
			sum+=(t%(tt*10)-t%tt)/tt*v;
			v*=t;
			tt*=10;
		}
		return sum;
	}
	
	static long so(long n) {
		for(long i=2;i*i<=n;i++) {
			if(n%i==0) {
				return i;
			}
		}
		return 0;
		
	}
	
	
	    
	     static void nibun(int a,int b,int target) {   
	    	 
	    	 int ok=a;
	    	 int ng=b;
	    	 
	    	 
	    	 int t=2;
	    	 
	    	 while(a<b) {
	    		 int G=(ok+ng)/2;
	    		 if(t==target) {
	    			 break;
	    		 }
	    		 if(t>ok) {
	    			 
	    		 }
	    		 if(t>ng) {
	    			 
	    		 }
	    		 
	    		 
	    		 
	    	 }
	    	 
	    	 
	    	 
	     }
	        
	    
	    

	
		//StringBuffer str = new StringBuffer(sc.nextInt());
		//for(int i=0;i<N;i++) {}
    
		
		
				
			//	p("===================");
				//for(int f:gyo.keySet()){
				    //p(gyo.get(f));
			//	}
			//	p("===================");
				
	           
		
		
		
		
		

	
	
	


	
	static void p(String ans) {out.println(ans);};
	static void p(int ans) {out.println(ans);};
	static void p() {out.println();};
	static void p(long ans) {out.println(ans);};
	static void p(double ans) {out.println(ans);};
	
	static void pn(String ans) {out.print(ans);};
	static void pn(int ans) {out.print(ans);};
	static void pn() {out.print("");};
	static void pn(long ans) {out.print(ans);};
	static void pn(double ans) {out.print(ans);};
	
	static class FastScanner {
	    private final InputStream in = System.in;
	    private final byte[] buffer = new byte[1024];
	    private int ptr = 0;
	    private int buflen = 0;

	    private boolean hasNextByte() {
	      if (ptr < buflen) {
	        return true;
	      } else {
	        ptr = 0;
	        try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        }
	        if (buflen <= 0) {
	          return false;
	        }
	      }
	      return true;
	    }

	    private int readByte() {
	      if (hasNextByte()) return buffer[ptr++];
	      else return -1;
	    }

	    private static boolean isPrintableChar(int c) {
	      return 33 <= c && c <= 126;
	    }

	    private void skipUnprintable() {
	      while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
	    }

	    public boolean hasNext() {
	      skipUnprintable();
	      return hasNextByte();
	    }

	    public String next() {
	      if (!hasNext()) throw new NoSuchElementException();
	      StringBuilder sb = new StringBuilder();
	      int b = readByte();
	      while (isPrintableChar(b)) {
	        sb.appendCodePoint(b);
	        b = readByte();
	      }
	      return sb.toString();
	    }

	    public long nextLong() {
	      if (!hasNext()) throw new NoSuchElementException();
	      long n = 0;
	      boolean minus = false;
	      int b = readByte();
	      if (b == '-') {
	        minus = true;
	        b = readByte();
	      }
	      if (b < '0' || '9' < b) {
	        throw new NumberFormatException();
	      }
	      while (true) {
	        if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        }
	        b = readByte();
	      }
	    }

	    public int nextInt() {
	      return (int) nextLong();
	    }
	    
	    public double nextDouble(){
	    	return Double.parseDouble(next());
	    }

	    public int[] nextIntArray(int N, boolean oneBased) {
	      if (oneBased) {
	        int[] array = new int[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } else {
	        int[] array = new int[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      }
	    }

	    public long[] nextLongArray(int N, boolean oneBased) {
	      if (oneBased) {
	        long[] array = new long[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } else {
	        long[] array = new long[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      }
	    }
	  }
}
	 import java.io.IOException; IOException java.io import java.io.InputStream; InputStream java.io import java.io.PrintWriter; PrintWriter java.io import java.util.Arrays; Arrays java.util import java.util.NoSuchElementException; NoSuchElementException java.util public class Main {
	public static void main(String[] args) {
		
		
		slover();
		out.flush();
	}
	static FastScanner sc = new FastScanner();
	static PrintWriter out = new PrintWriter(System.out);
	//StringBuffer S = new StringBuffer(sc.next());
	//String hoge2 = str.reverse().toString();
	//map.containsKey(A)
	//Map<Integer, Integer> map = new HashMap<Integer, Integer>(N);
	/*for ( キーのデータ型 key : マップの名前.keySet() ) {
		データのデータ型 data = マップの名前.get( key );
		
		// keyやdataを使った処理;
	}*/
	//int i = Integer.parseInt(s);
	//Queue<String> qq=new ArrayDeque<>(); //add,poll,peek BFSは前から実行される
	//Deque<String> dd=new ArrayDeque<>();//push後ろに入れる,poll(pop)後ろからとる,peek addは先頭に入るからバグ注意 
	//stackdfsは後ろから実行される
	//ArrayList<Integer> cc = new ArrayList<>(N);
	//cc.contains(tmp)
	//Arrays.asList(c).contains("a")
	//list.set(1,"walk");//1 1 2 3 5

	

	static int INF=(int) (Math.pow(10, 9)+7);
	
	private static int slover() {
		int N=sc.nextInt();
		
		int p[]=sc.nextIntArray(N, false);
		
		int v[]=p.clone();
		
		Arrays.parallelSort(v);
		int t=0;
		for(int i=0;i<N;i++) {
			
			if(p[i]!=v[i])t++;
			
			
		}
		//p(t);
		p(t==2||t==0 ? "YES":"NO");
		
		return 0;
		
		
	}
	
	
	
	
	
	
	static long Nsin(long t) {
		long sum=0;
		long v=1;
		long tt=1;
		for(long k=0;k<(t+"").length();k++) {
			sum+=(t%(tt*10)-t%tt)/tt*v;
			v*=t;
			tt*=10;
		}
		return sum;
	}
	
	static long so(long n) {
		for(long i=2;i*i<=n;i++) {
			if(n%i==0) {
				return i;
			}
		}
		return 0;
		
	}
	
	
	    
	     static void nibun(int a,int b,int target) {   
	    	 
	    	 int ok=a;
	    	 int ng=b;
	    	 
	    	 
	    	 int t=2;
	    	 
	    	 while(a<b) {
	    		 int G=(ok+ng)/2;
	    		 if(t==target) {
	    			 break;
	    		 }
	    		 if(t>ok) {
	    			 
	    		 }
	    		 if(t>ng) {
	    			 
	    		 }
	    		 
	    		 
	    		 
	    	 }
	    	 
	    	 
	    	 
	     }
	        
	    
	    

	
		//StringBuffer str = new StringBuffer(sc.nextInt());
		//for(int i=0;i<N;i++) {}
    
		
		
				
			//	p("===================");
				//for(int f:gyo.keySet()){
				    //p(gyo.get(f));
			//	}
			//	p("===================");
				
	           
		
		
		
		
		

	
	
	


	
	static void p(String ans) {out.println(ans);};
	static void p(int ans) {out.println(ans);};
	static void p() {out.println();};
	static void p(long ans) {out.println(ans);};
	static void p(double ans) {out.println(ans);};
	
	static void pn(String ans) {out.print(ans);};
	static void pn(int ans) {out.print(ans);};
	static void pn() {out.print("");};
	static void pn(long ans) {out.print(ans);};
	static void pn(double ans) {out.print(ans);};
	
	static class FastScanner {
	    private final InputStream in = System.in;
	    private final byte[] buffer = new byte[1024];
	    private int ptr = 0;
	    private int buflen = 0;

	    private boolean hasNextByte() {
	      if (ptr < buflen) {
	        return true;
	      } else {
	        ptr = 0;
	        try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        }
	        if (buflen <= 0) {
	          return false;
	        }
	      }
	      return true;
	    }

	    private int readByte() {
	      if (hasNextByte()) return buffer[ptr++];
	      else return -1;
	    }

	    private static boolean isPrintableChar(int c) {
	      return 33 <= c && c <= 126;
	    }

	    private void skipUnprintable() {
	      while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
	    }

	    public boolean hasNext() {
	      skipUnprintable();
	      return hasNextByte();
	    }

	    public String next() {
	      if (!hasNext()) throw new NoSuchElementException();
	      StringBuilder sb = new StringBuilder();
	      int b = readByte();
	      while (isPrintableChar(b)) {
	        sb.appendCodePoint(b);
	        b = readByte();
	      }
	      return sb.toString();
	    }

	    public long nextLong() {
	      if (!hasNext()) throw new NoSuchElementException();
	      long n = 0;
	      boolean minus = false;
	      int b = readByte();
	      if (b == '-') {
	        minus = true;
	        b = readByte();
	      }
	      if (b < '0' || '9' < b) {
	        throw new NumberFormatException();
	      }
	      while (true) {
	        if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        }
	        b = readByte();
	      }
	    }

	    public int nextInt() {
	      return (int) nextLong();
	    }
	    
	    public double nextDouble(){
	    	return Double.parseDouble(next());
	    }

	    public int[] nextIntArray(int N, boolean oneBased) {
	      if (oneBased) {
	        int[] array = new int[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } else {
	        int[] array = new int[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      }
	    }

	    public long[] nextLongArray(int N, boolean oneBased) {
	      if (oneBased) {
	        long[] array = new long[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } else {
	        long[] array = new long[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      }
	    }
	  }
} Main static FastScanner sc = new FastScanner(); sc new FastScanner() static PrintWriter out = new PrintWriter(System.out); out new PrintWriter(System.out) static int INF=(int) (Math.pow(10, 9)+7); INF (int) (Math.pow(10, 9)+7) Math.pow(10, 9) Math.pow Math 10 9 7 public static void main(String[] args) {
		
		
		slover();
		out.flush();
	} main {
		
		
		slover();
		out.flush();
	} slover() slover out.flush() out.flush out String[] args args private static int slover() {
		int N=sc.nextInt();
		
		int p[]=sc.nextIntArray(N, false);
		
		int v[]=p.clone();
		
		Arrays.parallelSort(v);
		int t=0;
		for(int i=0;i<N;i++) {
			
			if(p[i]!=v[i])t++;
			
			
		}
		//p(t);
		p(t==2||t==0 ? "YES":"NO");
		
		return 0;
		
		
	} slover {
		int N=sc.nextInt();
		
		int p[]=sc.nextIntArray(N, false);
		
		int v[]=p.clone();
		
		Arrays.parallelSort(v);
		int t=0;
		for(int i=0;i<N;i++) {
			
			if(p[i]!=v[i])t++;
			
			
		}
		//p(t);
		p(t==2||t==0 ? "YES":"NO");
		
		return 0;
		
		
	} int N=sc.nextInt(); N sc.nextInt() sc.nextInt sc int p[]=sc.nextIntArray(N, false); p sc.nextIntArray(N, false) sc.nextIntArray sc N false int v[]=p.clone(); v p.clone() p.clone p Arrays.parallelSort(v) Arrays.parallelSort Arrays v int t=0; t 0 for(int i=0;i<N;i++) {
			
			if(p[i]!=v[i])t++;
			
			
		} int i=0; int i=0; i 0 i<N i N i++ i++ i {
			
			if(p[i]!=v[i])t++;
			
			
		} {
			
			if(p[i]!=v[i])t++;
			
			
		} if(p[i]!=v[i])t++; p[i]!=v[i] p[i] p i v[i] v i t++ t p(t==2||t==0 ? "YES":"NO") p t==2||t==0 ? "YES":"NO" t==2||t==0 t==2 t 2 t==0 t 0 "YES" "NO" return 0; 0 static long Nsin(long t) {
		long sum=0;
		long v=1;
		long tt=1;
		for(long k=0;k<(t+"").length();k++) {
			sum+=(t%(tt*10)-t%tt)/tt*v;
			v*=t;
			tt*=10;
		}
		return sum;
	} Nsin {
		long sum=0;
		long v=1;
		long tt=1;
		for(long k=0;k<(t+"").length();k++) {
			sum+=(t%(tt*10)-t%tt)/tt*v;
			v*=t;
			tt*=10;
		}
		return sum;
	} long sum=0; sum 0 long v=1; v 1 long tt=1; tt 1 for(long k=0;k<(t+"").length();k++) {
			sum+=(t%(tt*10)-t%tt)/tt*v;
			v*=t;
			tt*=10;
		} long k=0; long k=0; k 0 k<(t+"").length() k (t+"").length() (t+"").length (t+"") t "" k++ k++ k {
			sum+=(t%(tt*10)-t%tt)/tt*v;
			v*=t;
			tt*=10;
		} {
			sum+=(t%(tt*10)-t%tt)/tt*v;
			v*=t;
			tt*=10;
		} sum+=(t%(tt*10)-t%tt)/tt*v sum (t%(tt*10)-t%tt)/tt*v (t%(tt*10)-t%tt)/tt (t%(tt*10)-t%tt) t%(tt*10) t (tt*10) tt 10 t%tt t tt tt v v*=t v t tt*=10 tt 10 return sum; sum long t t static long so(long n) {
		for(long i=2;i*i<=n;i++) {
			if(n%i==0) {
				return i;
			}
		}
		return 0;
		
	} so {
		for(long i=2;i*i<=n;i++) {
			if(n%i==0) {
				return i;
			}
		}
		return 0;
		
	} for(long i=2;i*i<=n;i++) {
			if(n%i==0) {
				return i;
			}
		} long i=2; long i=2; i 2 i*i<=n i*i i i n i++ i++ i {
			if(n%i==0) {
				return i;
			}
		} {
			if(n%i==0) {
				return i;
			}
		} if(n%i==0) {
				return i;
			} n%i==0 n%i n i 0 {
				return i;
			} return i; i return 0; 0 long n n static void nibun(int a,int b,int target) {   
	    	 
	    	 int ok=a;
	    	 int ng=b;
	    	 
	    	 
	    	 int t=2;
	    	 
	    	 while(a<b) {
	    		 int G=(ok+ng)/2;
	    		 if(t==target) {
	    			 break;
	    		 }
	    		 if(t>ok) {
	    			 
	    		 }
	    		 if(t>ng) {
	    			 
	    		 }
	    		 
	    		 
	    		 
	    	 }
	    	 
	    	 
	    	 
	     } nibun {   
	    	 
	    	 int ok=a;
	    	 int ng=b;
	    	 
	    	 
	    	 int t=2;
	    	 
	    	 while(a<b) {
	    		 int G=(ok+ng)/2;
	    		 if(t==target) {
	    			 break;
	    		 }
	    		 if(t>ok) {
	    			 
	    		 }
	    		 if(t>ng) {
	    			 
	    		 }
	    		 
	    		 
	    		 
	    	 }
	    	 
	    	 
	    	 
	     } int ok=a; ok a int ng=b; ng b int t=2; t 2 while(a<b) {
	    		 int G=(ok+ng)/2;
	    		 if(t==target) {
	    			 break;
	    		 }
	    		 if(t>ok) {
	    			 
	    		 }
	    		 if(t>ng) {
	    			 
	    		 }
	    		 
	    		 
	    		 
	    	 } a<b a b {
	    		 int G=(ok+ng)/2;
	    		 if(t==target) {
	    			 break;
	    		 }
	    		 if(t>ok) {
	    			 
	    		 }
	    		 if(t>ng) {
	    			 
	    		 }
	    		 
	    		 
	    		 
	    	 } int G=(ok+ng)/2; G (ok+ng)/2 (ok+ng) ok ng 2 if(t==target) {
	    			 break;
	    		 } t==target t target {
	    			 break;
	    		 } break; if(t>ok) {
	    			 
	    		 } t>ok t ok {
	    			 
	    		 } if(t>ng) {
	    			 
	    		 } t>ng t ng {
	    			 
	    		 } int a a int b b int target target static void p(String ans) {out.println(ans);} p {out.println(ans);} out.println(ans) out.println out ans String ans ans static void p(int ans) {out.println(ans);} p {out.println(ans);} out.println(ans) out.println out ans int ans ans static void p() {out.println();} p {out.println();} out.println() out.println out static void p(long ans) {out.println(ans);} p {out.println(ans);} out.println(ans) out.println out ans long ans ans static void p(double ans) {out.println(ans);} p {out.println(ans);} out.println(ans) out.println out ans double ans ans static void pn(String ans) {out.print(ans);} pn {out.print(ans);} out.print(ans) out.print out ans String ans ans static void pn(int ans) {out.print(ans);} pn {out.print(ans);} out.print(ans) out.print out ans int ans ans static void pn() {out.print("");} pn {out.print("");} out.print("") out.print out "" static void pn(long ans) {out.print(ans);} pn {out.print(ans);} out.print(ans) out.print out ans long ans ans static void pn(double ans) {out.print(ans);} pn {out.print(ans);} out.print(ans) out.print out ans double ans ans static class FastScanner {
	    private final InputStream in = System.in;
	    private final byte[] buffer = new byte[1024];
	    private int ptr = 0;
	    private int buflen = 0;

	    private boolean hasNextByte() {
	      if (ptr < buflen) {
	        return true;
	      } else {
	        ptr = 0;
	        try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        }
	        if (buflen <= 0) {
	          return false;
	        }
	      }
	      return true;
	    }

	    private int readByte() {
	      if (hasNextByte()) return buffer[ptr++];
	      else return -1;
	    }

	    private static boolean isPrintableChar(int c) {
	      return 33 <= c && c <= 126;
	    }

	    private void skipUnprintable() {
	      while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
	    }

	    public boolean hasNext() {
	      skipUnprintable();
	      return hasNextByte();
	    }

	    public String next() {
	      if (!hasNext()) throw new NoSuchElementException();
	      StringBuilder sb = new StringBuilder();
	      int b = readByte();
	      while (isPrintableChar(b)) {
	        sb.appendCodePoint(b);
	        b = readByte();
	      }
	      return sb.toString();
	    }

	    public long nextLong() {
	      if (!hasNext()) throw new NoSuchElementException();
	      long n = 0;
	      boolean minus = false;
	      int b = readByte();
	      if (b == '-') {
	        minus = true;
	        b = readByte();
	      }
	      if (b < '0' || '9' < b) {
	        throw new NumberFormatException();
	      }
	      while (true) {
	        if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        }
	        b = readByte();
	      }
	    }

	    public int nextInt() {
	      return (int) nextLong();
	    }
	    
	    public double nextDouble(){
	    	return Double.parseDouble(next());
	    }

	    public int[] nextIntArray(int N, boolean oneBased) {
	      if (oneBased) {
	        int[] array = new int[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } else {
	        int[] array = new int[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      }
	    }

	    public long[] nextLongArray(int N, boolean oneBased) {
	      if (oneBased) {
	        long[] array = new long[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } else {
	        long[] array = new long[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      }
	    }
	  } FastScanner private final InputStream in = System.in; in System.in System System.in private final byte[] buffer = new byte[1024]; buffer new byte[1024] 1024 private int ptr = 0; ptr 0 private int buflen = 0; buflen 0 private boolean hasNextByte() {
	      if (ptr < buflen) {
	        return true;
	      } else {
	        ptr = 0;
	        try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        }
	        if (buflen <= 0) {
	          return false;
	        }
	      }
	      return true;
	    } hasNextByte {
	      if (ptr < buflen) {
	        return true;
	      } else {
	        ptr = 0;
	        try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        }
	        if (buflen <= 0) {
	          return false;
	        }
	      }
	      return true;
	    } if (ptr < buflen) {
	        return true;
	      } else {
	        ptr = 0;
	        try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        }
	        if (buflen <= 0) {
	          return false;
	        }
	      } ptr < buflen ptr buflen {
	        return true;
	      } return true; true {
	        ptr = 0;
	        try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        }
	        if (buflen <= 0) {
	          return false;
	        }
	      } ptr = 0 ptr 0 try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        } catch (IOException e) {
	          e.printStackTrace();
	        } IOException e {
	          e.printStackTrace();
	        } e.printStackTrace() e.printStackTrace e {
	          buflen = in.read(buffer);
	        } buflen = in.read(buffer) buflen in.read(buffer) in.read in buffer if (buflen <= 0) {
	          return false;
	        } buflen <= 0 buflen 0 {
	          return false;
	        } return false; false return true; true private int readByte() {
	      if (hasNextByte()) return buffer[ptr++];
	      else return -1;
	    } readByte {
	      if (hasNextByte()) return buffer[ptr++];
	      else return -1;
	    } if (hasNextByte()) return buffer[ptr++];
	      else return -1; hasNextByte() hasNextByte return buffer[ptr++]; buffer[ptr++] buffer ptr++ ptr return -1; -1 1 private static boolean isPrintableChar(int c) {
	      return 33 <= c && c <= 126;
	    } isPrintableChar {
	      return 33 <= c && c <= 126;
	    } return 33 <= c && c <= 126; 33 <= c && c <= 126 33 <= c 33 c c <= 126 c 126 int c c private void skipUnprintable() {
	      while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
	    } skipUnprintable {
	      while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
	    } while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; hasNextByte() && !isPrintableChar(buffer[ptr]) hasNextByte() hasNextByte !isPrintableChar(buffer[ptr]) isPrintableChar(buffer[ptr]) isPrintableChar buffer[ptr] buffer ptr ptr++ ptr public boolean hasNext() {
	      skipUnprintable();
	      return hasNextByte();
	    } hasNext {
	      skipUnprintable();
	      return hasNextByte();
	    } skipUnprintable() skipUnprintable return hasNextByte(); hasNextByte() hasNextByte public String next() {
	      if (!hasNext()) throw new NoSuchElementException();
	      StringBuilder sb = new StringBuilder();
	      int b = readByte();
	      while (isPrintableChar(b)) {
	        sb.appendCodePoint(b);
	        b = readByte();
	      }
	      return sb.toString();
	    } next {
	      if (!hasNext()) throw new NoSuchElementException();
	      StringBuilder sb = new StringBuilder();
	      int b = readByte();
	      while (isPrintableChar(b)) {
	        sb.appendCodePoint(b);
	        b = readByte();
	      }
	      return sb.toString();
	    } if (!hasNext()) throw new NoSuchElementException(); !hasNext() hasNext() hasNext throw new NoSuchElementException(); new NoSuchElementException() StringBuilder sb = new StringBuilder(); sb new StringBuilder() int b = readByte(); b readByte() readByte while (isPrintableChar(b)) {
	        sb.appendCodePoint(b);
	        b = readByte();
	      } isPrintableChar(b) isPrintableChar b {
	        sb.appendCodePoint(b);
	        b = readByte();
	      } sb.appendCodePoint(b) sb.appendCodePoint sb b b = readByte() b readByte() readByte return sb.toString(); sb.toString() sb.toString sb public long nextLong() {
	      if (!hasNext()) throw new NoSuchElementException();
	      long n = 0;
	      boolean minus = false;
	      int b = readByte();
	      if (b == '-') {
	        minus = true;
	        b = readByte();
	      }
	      if (b < '0' || '9' < b) {
	        throw new NumberFormatException();
	      }
	      while (true) {
	        if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        }
	        b = readByte();
	      }
	    } nextLong {
	      if (!hasNext()) throw new NoSuchElementException();
	      long n = 0;
	      boolean minus = false;
	      int b = readByte();
	      if (b == '-') {
	        minus = true;
	        b = readByte();
	      }
	      if (b < '0' || '9' < b) {
	        throw new NumberFormatException();
	      }
	      while (true) {
	        if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        }
	        b = readByte();
	      }
	    } if (!hasNext()) throw new NoSuchElementException(); !hasNext() hasNext() hasNext throw new NoSuchElementException(); new NoSuchElementException() long n = 0; n 0 boolean minus = false; minus false int b = readByte(); b readByte() readByte if (b == '-') {
	        minus = true;
	        b = readByte();
	      } b == '-' b '-' {
	        minus = true;
	        b = readByte();
	      } minus = true minus true b = readByte() b readByte() readByte if (b < '0' || '9' < b) {
	        throw new NumberFormatException();
	      } b < '0' || '9' < b b < '0' b '0' '9' < b '9' b {
	        throw new NumberFormatException();
	      } throw new NumberFormatException(); new NumberFormatException() while (true) {
	        if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        }
	        b = readByte();
	      } true {
	        if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        }
	        b = readByte();
	      } if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        } '0' <= b && b <= '9' '0' <= b '0' b b <= '9' b '9' {
	          n *= 10;
	          n += b - '0';
	        } n *= 10 n 10 n += b - '0' n b - '0' b '0' if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        } b == -1 || !isPrintableChar(b) b == -1 b -1 1 !isPrintableChar(b) isPrintableChar(b) isPrintableChar b {
	          return minus ? -n : n;
	        } return minus ? -n : n; minus ? -n : n minus -n n n {
	          throw new NumberFormatException();
	        } throw new NumberFormatException(); new NumberFormatException() b = readByte() b readByte() readByte public int nextInt() {
	      return (int) nextLong();
	    } nextInt {
	      return (int) nextLong();
	    } return (int) nextLong(); (int) nextLong() nextLong public double nextDouble(){
	    	return Double.parseDouble(next());
	    } nextDouble {
	    	return Double.parseDouble(next());
	    } return Double.parseDouble(next()); Double.parseDouble(next()) Double.parseDouble Double next() next public int[] nextIntArray(int N, boolean oneBased) {
	      if (oneBased) {
	        int[] array = new int[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } else {
	        int[] array = new int[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      }
	    } nextIntArray {
	      if (oneBased) {
	        int[] array = new int[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } else {
	        int[] array = new int[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      }
	    } if (oneBased) {
	        int[] array = new int[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } else {
	        int[] array = new int[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } oneBased {
	        int[] array = new int[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } int[] array = new int[N + 1]; array new int[N + 1] N + 1 N 1 for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        } int i = 1; int i = 1; i 1 i <= N i N i++ i++ i {
	          array[i] = sc.nextInt();
	        } {
	          array[i] = sc.nextInt();
	        } array[i] = sc.nextInt() array[i] array i sc.nextInt() sc.nextInt sc return array; array {
	        int[] array = new int[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } int[] array = new int[N]; array new int[N] N for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        } int i = 0; int i = 0; i 0 i < N i N i++ i++ i {
	          array[i] = sc.nextInt();
	        } {
	          array[i] = sc.nextInt();
	        } array[i] = sc.nextInt() array[i] array i sc.nextInt() sc.nextInt sc return array; array int N N boolean oneBased oneBased public long[] nextLongArray(int N, boolean oneBased) {
	      if (oneBased) {
	        long[] array = new long[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } else {
	        long[] array = new long[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      }
	    } nextLongArray {
	      if (oneBased) {
	        long[] array = new long[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } else {
	        long[] array = new long[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      }
	    } if (oneBased) {
	        long[] array = new long[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } else {
	        long[] array = new long[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } oneBased {
	        long[] array = new long[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } long[] array = new long[N + 1]; array new long[N + 1] N + 1 N 1 for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        } int i = 1; int i = 1; i 1 i <= N i N i++ i++ i {
	          array[i] = sc.nextLong();
	        } {
	          array[i] = sc.nextLong();
	        } array[i] = sc.nextLong() array[i] array i sc.nextLong() sc.nextLong sc return array; array {
	        long[] array = new long[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } long[] array = new long[N]; array new long[N] N for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        } int i = 0; int i = 0; i 0 i < N i N i++ i++ i {
	          array[i] = sc.nextLong();
	        } {
	          array[i] = sc.nextLong();
	        } array[i] = sc.nextLong() array[i] array i sc.nextLong() sc.nextLong sc return array; array int N N boolean oneBased oneBased public class Main {
	public static void main(String[] args) {
		
		
		slover();
		out.flush();
	}
	static FastScanner sc = new FastScanner();
	static PrintWriter out = new PrintWriter(System.out);
	//StringBuffer S = new StringBuffer(sc.next());
	//String hoge2 = str.reverse().toString();
	//map.containsKey(A)
	//Map<Integer, Integer> map = new HashMap<Integer, Integer>(N);
	/*for ( キーのデータ型 key : マップの名前.keySet() ) {
		データのデータ型 data = マップの名前.get( key );
		
		// keyやdataを使った処理;
	}*/
	//int i = Integer.parseInt(s);
	//Queue<String> qq=new ArrayDeque<>(); //add,poll,peek BFSは前から実行される
	//Deque<String> dd=new ArrayDeque<>();//push後ろに入れる,poll(pop)後ろからとる,peek addは先頭に入るからバグ注意 
	//stackdfsは後ろから実行される
	//ArrayList<Integer> cc = new ArrayList<>(N);
	//cc.contains(tmp)
	//Arrays.asList(c).contains("a")
	//list.set(1,"walk");//1 1 2 3 5

	

	static int INF=(int) (Math.pow(10, 9)+7);
	
	private static int slover() {
		int N=sc.nextInt();
		
		int p[]=sc.nextIntArray(N, false);
		
		int v[]=p.clone();
		
		Arrays.parallelSort(v);
		int t=0;
		for(int i=0;i<N;i++) {
			
			if(p[i]!=v[i])t++;
			
			
		}
		//p(t);
		p(t==2||t==0 ? "YES":"NO");
		
		return 0;
		
		
	}
	
	
	
	
	
	
	static long Nsin(long t) {
		long sum=0;
		long v=1;
		long tt=1;
		for(long k=0;k<(t+"").length();k++) {
			sum+=(t%(tt*10)-t%tt)/tt*v;
			v*=t;
			tt*=10;
		}
		return sum;
	}
	
	static long so(long n) {
		for(long i=2;i*i<=n;i++) {
			if(n%i==0) {
				return i;
			}
		}
		return 0;
		
	}
	
	
	    
	     static void nibun(int a,int b,int target) {   
	    	 
	    	 int ok=a;
	    	 int ng=b;
	    	 
	    	 
	    	 int t=2;
	    	 
	    	 while(a<b) {
	    		 int G=(ok+ng)/2;
	    		 if(t==target) {
	    			 break;
	    		 }
	    		 if(t>ok) {
	    			 
	    		 }
	    		 if(t>ng) {
	    			 
	    		 }
	    		 
	    		 
	    		 
	    	 }
	    	 
	    	 
	    	 
	     }
	        
	    
	    

	
		//StringBuffer str = new StringBuffer(sc.nextInt());
		//for(int i=0;i<N;i++) {}
    
		
		
				
			//	p("===================");
				//for(int f:gyo.keySet()){
				    //p(gyo.get(f));
			//	}
			//	p("===================");
				
	           
		
		
		
		
		

	
	
	


	
	static void p(String ans) {out.println(ans);};
	static void p(int ans) {out.println(ans);};
	static void p() {out.println();};
	static void p(long ans) {out.println(ans);};
	static void p(double ans) {out.println(ans);};
	
	static void pn(String ans) {out.print(ans);};
	static void pn(int ans) {out.print(ans);};
	static void pn() {out.print("");};
	static void pn(long ans) {out.print(ans);};
	static void pn(double ans) {out.print(ans);};
	
	static class FastScanner {
	    private final InputStream in = System.in;
	    private final byte[] buffer = new byte[1024];
	    private int ptr = 0;
	    private int buflen = 0;

	    private boolean hasNextByte() {
	      if (ptr < buflen) {
	        return true;
	      } else {
	        ptr = 0;
	        try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        }
	        if (buflen <= 0) {
	          return false;
	        }
	      }
	      return true;
	    }

	    private int readByte() {
	      if (hasNextByte()) return buffer[ptr++];
	      else return -1;
	    }

	    private static boolean isPrintableChar(int c) {
	      return 33 <= c && c <= 126;
	    }

	    private void skipUnprintable() {
	      while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
	    }

	    public boolean hasNext() {
	      skipUnprintable();
	      return hasNextByte();
	    }

	    public String next() {
	      if (!hasNext()) throw new NoSuchElementException();
	      StringBuilder sb = new StringBuilder();
	      int b = readByte();
	      while (isPrintableChar(b)) {
	        sb.appendCodePoint(b);
	        b = readByte();
	      }
	      return sb.toString();
	    }

	    public long nextLong() {
	      if (!hasNext()) throw new NoSuchElementException();
	      long n = 0;
	      boolean minus = false;
	      int b = readByte();
	      if (b == '-') {
	        minus = true;
	        b = readByte();
	      }
	      if (b < '0' || '9' < b) {
	        throw new NumberFormatException();
	      }
	      while (true) {
	        if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        }
	        b = readByte();
	      }
	    }

	    public int nextInt() {
	      return (int) nextLong();
	    }
	    
	    public double nextDouble(){
	    	return Double.parseDouble(next());
	    }

	    public int[] nextIntArray(int N, boolean oneBased) {
	      if (oneBased) {
	        int[] array = new int[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } else {
	        int[] array = new int[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      }
	    }

	    public long[] nextLongArray(int N, boolean oneBased) {
	      if (oneBased) {
	        long[] array = new long[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } else {
	        long[] array = new long[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      }
	    }
	  }
} public class Main {
	public static void main(String[] args) {
		
		
		slover();
		out.flush();
	}
	static FastScanner sc = new FastScanner();
	static PrintWriter out = new PrintWriter(System.out);
	//StringBuffer S = new StringBuffer(sc.next());
	//String hoge2 = str.reverse().toString();
	//map.containsKey(A)
	//Map<Integer, Integer> map = new HashMap<Integer, Integer>(N);
	/*for ( キーのデータ型 key : マップの名前.keySet() ) {
		データのデータ型 data = マップの名前.get( key );
		
		// keyやdataを使った処理;
	}*/
	//int i = Integer.parseInt(s);
	//Queue<String> qq=new ArrayDeque<>(); //add,poll,peek BFSは前から実行される
	//Deque<String> dd=new ArrayDeque<>();//push後ろに入れる,poll(pop)後ろからとる,peek addは先頭に入るからバグ注意 
	//stackdfsは後ろから実行される
	//ArrayList<Integer> cc = new ArrayList<>(N);
	//cc.contains(tmp)
	//Arrays.asList(c).contains("a")
	//list.set(1,"walk");//1 1 2 3 5

	

	static int INF=(int) (Math.pow(10, 9)+7);
	
	private static int slover() {
		int N=sc.nextInt();
		
		int p[]=sc.nextIntArray(N, false);
		
		int v[]=p.clone();
		
		Arrays.parallelSort(v);
		int t=0;
		for(int i=0;i<N;i++) {
			
			if(p[i]!=v[i])t++;
			
			
		}
		//p(t);
		p(t==2||t==0 ? "YES":"NO");
		
		return 0;
		
		
	}
	
	
	
	
	
	
	static long Nsin(long t) {
		long sum=0;
		long v=1;
		long tt=1;
		for(long k=0;k<(t+"").length();k++) {
			sum+=(t%(tt*10)-t%tt)/tt*v;
			v*=t;
			tt*=10;
		}
		return sum;
	}
	
	static long so(long n) {
		for(long i=2;i*i<=n;i++) {
			if(n%i==0) {
				return i;
			}
		}
		return 0;
		
	}
	
	
	    
	     static void nibun(int a,int b,int target) {   
	    	 
	    	 int ok=a;
	    	 int ng=b;
	    	 
	    	 
	    	 int t=2;
	    	 
	    	 while(a<b) {
	    		 int G=(ok+ng)/2;
	    		 if(t==target) {
	    			 break;
	    		 }
	    		 if(t>ok) {
	    			 
	    		 }
	    		 if(t>ng) {
	    			 
	    		 }
	    		 
	    		 
	    		 
	    	 }
	    	 
	    	 
	    	 
	     }
	        
	    
	    

	
		//StringBuffer str = new StringBuffer(sc.nextInt());
		//for(int i=0;i<N;i++) {}
    
		
		
				
			//	p("===================");
				//for(int f:gyo.keySet()){
				    //p(gyo.get(f));
			//	}
			//	p("===================");
				
	           
		
		
		
		
		

	
	
	


	
	static void p(String ans) {out.println(ans);};
	static void p(int ans) {out.println(ans);};
	static void p() {out.println();};
	static void p(long ans) {out.println(ans);};
	static void p(double ans) {out.println(ans);};
	
	static void pn(String ans) {out.print(ans);};
	static void pn(int ans) {out.print(ans);};
	static void pn() {out.print("");};
	static void pn(long ans) {out.print(ans);};
	static void pn(double ans) {out.print(ans);};
	
	static class FastScanner {
	    private final InputStream in = System.in;
	    private final byte[] buffer = new byte[1024];
	    private int ptr = 0;
	    private int buflen = 0;

	    private boolean hasNextByte() {
	      if (ptr < buflen) {
	        return true;
	      } else {
	        ptr = 0;
	        try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        }
	        if (buflen <= 0) {
	          return false;
	        }
	      }
	      return true;
	    }

	    private int readByte() {
	      if (hasNextByte()) return buffer[ptr++];
	      else return -1;
	    }

	    private static boolean isPrintableChar(int c) {
	      return 33 <= c && c <= 126;
	    }

	    private void skipUnprintable() {
	      while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
	    }

	    public boolean hasNext() {
	      skipUnprintable();
	      return hasNextByte();
	    }

	    public String next() {
	      if (!hasNext()) throw new NoSuchElementException();
	      StringBuilder sb = new StringBuilder();
	      int b = readByte();
	      while (isPrintableChar(b)) {
	        sb.appendCodePoint(b);
	        b = readByte();
	      }
	      return sb.toString();
	    }

	    public long nextLong() {
	      if (!hasNext()) throw new NoSuchElementException();
	      long n = 0;
	      boolean minus = false;
	      int b = readByte();
	      if (b == '-') {
	        minus = true;
	        b = readByte();
	      }
	      if (b < '0' || '9' < b) {
	        throw new NumberFormatException();
	      }
	      while (true) {
	        if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        }
	        b = readByte();
	      }
	    }

	    public int nextInt() {
	      return (int) nextLong();
	    }
	    
	    public double nextDouble(){
	    	return Double.parseDouble(next());
	    }

	    public int[] nextIntArray(int N, boolean oneBased) {
	      if (oneBased) {
	        int[] array = new int[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } else {
	        int[] array = new int[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      }
	    }

	    public long[] nextLongArray(int N, boolean oneBased) {
	      if (oneBased) {
	        long[] array = new long[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } else {
	        long[] array = new long[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      }
	    }
	  }
} Main
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.NoSuchElementException;


public class Main {
	public static void main(String[] args) {
		
		
		slover();
		out.flush();
	}
	static FastScanner sc = new FastScanner();
	static PrintWriter out = new PrintWriter(System.out);
	//StringBuffer S = new StringBuffer(sc.next());
	//String hoge2 = str.reverse().toString();
	//map.containsKey(A)
	//Map<Integer, Integer> map = new HashMap<Integer, Integer>(N);
	/*for ( キーのデータ型 key : マップの名前.keySet() ) {
		データのデータ型 data = マップの名前.get( key );
		
		// keyやdataを使った処理;
	}*/
	//int i = Integer.parseInt(s);
	//Queue<String> qq=new ArrayDeque<>(); //add,poll,peek BFSは前から実行される
	//Deque<String> dd=new ArrayDeque<>();//push後ろに入れる,poll(pop)後ろからとる,peek addは先頭に入るからバグ注意 
	//stackdfsは後ろから実行される
	//ArrayList<Integer> cc = new ArrayList<>(N);
	//cc.contains(tmp)
	//Arrays.asList(c).contains("a")
	//list.set(1,"walk");//1 1 2 3 5

	

	static int INF=(int) (Math.pow(10, 9)+7);
	
	private static int slover() {
		int N=sc.nextInt();
		
		int p[]=sc.nextIntArray(N, false);
		
		int v[]=p.clone();
		
		Arrays.parallelSort(v);
		int t=0;
		for(int i=0;i<N;i++) {
			
			if(p[i]!=v[i])t++;
			
			
		}
		//p(t);
		p(t==2||t==0 ? "YES":"NO");
		
		return 0;
		
		
	}
	
	
	
	
	
	
	static long Nsin(long t) {
		long sum=0;
		long v=1;
		long tt=1;
		for(long k=0;k<(t+"").length();k++) {
			sum+=(t%(tt*10)-t%tt)/tt*v;
			v*=t;
			tt*=10;
		}
		return sum;
	}
	
	static long so(long n) {
		for(long i=2;i*i<=n;i++) {
			if(n%i==0) {
				return i;
			}
		}
		return 0;
		
	}
	
	
	    
	     static void nibun(int a,int b,int target) {   
	    	 
	    	 int ok=a;
	    	 int ng=b;
	    	 
	    	 
	    	 int t=2;
	    	 
	    	 while(a<b) {
	    		 int G=(ok+ng)/2;
	    		 if(t==target) {
	    			 break;
	    		 }
	    		 if(t>ok) {
	    			 
	    		 }
	    		 if(t>ng) {
	    			 
	    		 }
	    		 
	    		 
	    		 
	    	 }
	    	 
	    	 
	    	 
	     }
	        
	    
	    

	
		//StringBuffer str = new StringBuffer(sc.nextInt());
		//for(int i=0;i<N;i++) {}
    
		
		
				
			//	p("===================");
				//for(int f:gyo.keySet()){
				    //p(gyo.get(f));
			//	}
			//	p("===================");
				
	           
		
		
		
		
		

	
	
	


	
	static void p(String ans) {out.println(ans);};
	static void p(int ans) {out.println(ans);};
	static void p() {out.println();};
	static void p(long ans) {out.println(ans);};
	static void p(double ans) {out.println(ans);};
	
	static void pn(String ans) {out.print(ans);};
	static void pn(int ans) {out.print(ans);};
	static void pn() {out.print("");};
	static void pn(long ans) {out.print(ans);};
	static void pn(double ans) {out.print(ans);};
	
	static class FastScanner {
	    private final InputStream in = System.in;
	    private final byte[] buffer = new byte[1024];
	    private int ptr = 0;
	    private int buflen = 0;

	    private boolean hasNextByte() {
	      if (ptr < buflen) {
	        return true;
	      } else {
	        ptr = 0;
	        try {
	          buflen = in.read(buffer);
	        } catch (IOException e) {
	          e.printStackTrace();
	        }
	        if (buflen <= 0) {
	          return false;
	        }
	      }
	      return true;
	    }

	    private int readByte() {
	      if (hasNextByte()) return buffer[ptr++];
	      else return -1;
	    }

	    private static boolean isPrintableChar(int c) {
	      return 33 <= c && c <= 126;
	    }

	    private void skipUnprintable() {
	      while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
	    }

	    public boolean hasNext() {
	      skipUnprintable();
	      return hasNextByte();
	    }

	    public String next() {
	      if (!hasNext()) throw new NoSuchElementException();
	      StringBuilder sb = new StringBuilder();
	      int b = readByte();
	      while (isPrintableChar(b)) {
	        sb.appendCodePoint(b);
	        b = readByte();
	      }
	      return sb.toString();
	    }

	    public long nextLong() {
	      if (!hasNext()) throw new NoSuchElementException();
	      long n = 0;
	      boolean minus = false;
	      int b = readByte();
	      if (b == '-') {
	        minus = true;
	        b = readByte();
	      }
	      if (b < '0' || '9' < b) {
	        throw new NumberFormatException();
	      }
	      while (true) {
	        if ('0' <= b && b <= '9') {
	          n *= 10;
	          n += b - '0';
	        } else if (b == -1 || !isPrintableChar(b)) {
	          return minus ? -n : n;
	        } else {
	          throw new NumberFormatException();
	        }
	        b = readByte();
	      }
	    }

	    public int nextInt() {
	      return (int) nextLong();
	    }
	    
	    public double nextDouble(){
	    	return Double.parseDouble(next());
	    }

	    public int[] nextIntArray(int N, boolean oneBased) {
	      if (oneBased) {
	        int[] array = new int[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      } else {
	        int[] array = new int[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextInt();
	        }
	        return array;
	      }
	    }

	    public long[] nextLongArray(int N, boolean oneBased) {
	      if (oneBased) {
	        long[] array = new long[N + 1];
	        for (int i = 1; i <= N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      } else {
	        long[] array = new long[N];
	        for (int i = 0; i < N; i++) {
	          array[i] = sc.nextLong();
	        }
	        return array;
	      }
	    }
	  }
}
	
