import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class Main {
	private static FastScanner sc = new FastScanner();

	public static void main(String[] args) {
		int n = sc.nextInt();		
		int ans = Integer.MIN_VALUE;
		
		int min = Integer.MAX_VALUE;
		for(int i=1; i<=n; i++){
			int R = sc.nextInt();
			
			if(R - min > ans){
				ans = R - min;
			}
			
			if(R < min){
				min = R;
			}
		}
		
		System.out.println(ans);
	}

	static class FastScanner {
        BufferedReader br;
        StringTokenizer st;

        public FastScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException  e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }
} import java.io.BufferedReader; BufferedReader java.io import java.io.IOException; IOException java.io import java.io.InputStreamReader; InputStreamReader java.io import java.util.StringTokenizer; StringTokenizer java.util public class Main {
	private static FastScanner sc = new FastScanner();

	public static void main(String[] args) {
		int n = sc.nextInt();		
		int ans = Integer.MIN_VALUE;
		
		int min = Integer.MAX_VALUE;
		for(int i=1; i<=n; i++){
			int R = sc.nextInt();
			
			if(R - min > ans){
				ans = R - min;
			}
			
			if(R < min){
				min = R;
			}
		}
		
		System.out.println(ans);
	}

	static class FastScanner {
        BufferedReader br;
        StringTokenizer st;

        public FastScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException  e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }
} Main private static FastScanner sc = new FastScanner(); sc new FastScanner() public static void main(String[] args) {
		int n = sc.nextInt();		
		int ans = Integer.MIN_VALUE;
		
		int min = Integer.MAX_VALUE;
		for(int i=1; i<=n; i++){
			int R = sc.nextInt();
			
			if(R - min > ans){
				ans = R - min;
			}
			
			if(R < min){
				min = R;
			}
		}
		
		System.out.println(ans);
	} main {
		int n = sc.nextInt();		
		int ans = Integer.MIN_VALUE;
		
		int min = Integer.MAX_VALUE;
		for(int i=1; i<=n; i++){
			int R = sc.nextInt();
			
			if(R - min > ans){
				ans = R - min;
			}
			
			if(R < min){
				min = R;
			}
		}
		
		System.out.println(ans);
	} int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int ans = Integer.MIN_VALUE; ans Integer.MIN_VALUE Integer Integer.MIN_VALUE int min = Integer.MAX_VALUE; min Integer.MAX_VALUE Integer Integer.MAX_VALUE for(int i=1; i<=n; i++){
			int R = sc.nextInt();
			
			if(R - min > ans){
				ans = R - min;
			}
			
			if(R < min){
				min = R;
			}
		} int i=1; int i=1; i 1 i<=n i n i++ i++ i {
			int R = sc.nextInt();
			
			if(R - min > ans){
				ans = R - min;
			}
			
			if(R < min){
				min = R;
			}
		} {
			int R = sc.nextInt();
			
			if(R - min > ans){
				ans = R - min;
			}
			
			if(R < min){
				min = R;
			}
		} int R = sc.nextInt(); R sc.nextInt() sc.nextInt sc if(R - min > ans){
				ans = R - min;
			} R - min > ans R - min R min ans {
				ans = R - min;
			} ans = R - min ans R - min R min if(R < min){
				min = R;
			} R < min R min {
				min = R;
			} min = R min R System.out.println(ans) System.out.println System.out System System.out ans String[] args args static class FastScanner {
        BufferedReader br;
        StringTokenizer st;

        public FastScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException  e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    } FastScanner BufferedReader br; br StringTokenizer st; st public FastScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        } FastScanner {
            br = new BufferedReader(new InputStreamReader(System.in));
        } br = new BufferedReader(new InputStreamReader(System.in)) br new BufferedReader(new InputStreamReader(System.in)) String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException  e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        } next {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException  e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        } while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException  e) {
                    e.printStackTrace();
                }
            } st == null || !st.hasMoreElements() st == null st null !st.hasMoreElements() st.hasMoreElements() st.hasMoreElements st {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException  e) {
                    e.printStackTrace();
                }
            } try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException  e) {
                    e.printStackTrace();
                } catch (IOException  e) {
                    e.printStackTrace();
                } IOException  e {
                    e.printStackTrace();
                } e.printStackTrace() e.printStackTrace e {
                    st = new StringTokenizer(br.readLine());
                } st = new StringTokenizer(br.readLine()) st new StringTokenizer(br.readLine()) return st.nextToken(); st.nextToken() st.nextToken st int nextInt() {
            return Integer.parseInt(next());
        } nextInt {
            return Integer.parseInt(next());
        } return Integer.parseInt(next()); Integer.parseInt(next()) Integer.parseInt Integer next() next long nextLong() {
            return Long.parseLong(next());
        } nextLong {
            return Long.parseLong(next());
        } return Long.parseLong(next()); Long.parseLong(next()) Long.parseLong Long next() next double nextDouble() {
            return Double.parseDouble(next());
        } nextDouble {
            return Double.parseDouble(next());
        } return Double.parseDouble(next()); Double.parseDouble(next()) Double.parseDouble Double next() next String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        } nextLine {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        } String str = ""; str "" try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } IOException e {
                e.printStackTrace();
            } e.printStackTrace() e.printStackTrace e {
                str = br.readLine();
            } str = br.readLine() str br.readLine() br.readLine br return str; str public class Main {
	private static FastScanner sc = new FastScanner();

	public static void main(String[] args) {
		int n = sc.nextInt();		
		int ans = Integer.MIN_VALUE;
		
		int min = Integer.MAX_VALUE;
		for(int i=1; i<=n; i++){
			int R = sc.nextInt();
			
			if(R - min > ans){
				ans = R - min;
			}
			
			if(R < min){
				min = R;
			}
		}
		
		System.out.println(ans);
	}

	static class FastScanner {
        BufferedReader br;
        StringTokenizer st;

        public FastScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException  e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }
} public class Main {
	private static FastScanner sc = new FastScanner();

	public static void main(String[] args) {
		int n = sc.nextInt();		
		int ans = Integer.MIN_VALUE;
		
		int min = Integer.MAX_VALUE;
		for(int i=1; i<=n; i++){
			int R = sc.nextInt();
			
			if(R - min > ans){
				ans = R - min;
			}
			
			if(R < min){
				min = R;
			}
		}
		
		System.out.println(ans);
	}

	static class FastScanner {
        BufferedReader br;
        StringTokenizer st;

        public FastScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException  e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }
} Main
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class Main {
	private static FastScanner sc = new FastScanner();

	public static void main(String[] args) {
		int n = sc.nextInt();		
		int ans = Integer.MIN_VALUE;
		
		int min = Integer.MAX_VALUE;
		for(int i=1; i<=n; i++){
			int R = sc.nextInt();
			
			if(R - min > ans){
				ans = R - min;
			}
			
			if(R < min){
				min = R;
			}
		}
		
		System.out.println(ans);
	}

	static class FastScanner {
        BufferedReader br;
        StringTokenizer st;

        public FastScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException  e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }
}