44 58 90 53
 20 14 37 71
 4 2 4 2
 1 2 5 5
 1 2 8 9
 99 100 3 98
 92 69 83 97
 3 1 1 1
 18 88 18 18
 1 1 1 1
 69 7 44 30
 90 30 30 30
 1 2 3 5
 1 1 3 1
 6 3 6 6
 26 52 7 19
 6 4 8 6
 10 2 3 5
 34 11 84 39
 1 1 14 12
 3 2 1 1
 2 4 6 6
 1 1 2 1
 72 96 2 26
 97 95 91 27
 1 2 1 3
 1 1 2 3
 1 1 1 2
 1 1 10 20
 2 3 2 5
 1 2 10 7
 2 1 28 9
 4 4 4 8
 2 2 4 6
 72 52 62 62
 76 97 99 74
 100 100 99 100
 30 74 41 63
 5 10 1 6
 18 17 17 20
 2 4 1 1
 7 3 6 3
 1 1 4 5
 2 2 6 2
 1 2 6 3
 3 5 1 3
 70 100 10 86
 48 14 3 31
 2 6 3 2
 2 3 10 10
 4 4 12 4
 14 9 10 6
 100 98 99 97
 5 7 1 3
 1 1 4 2
 14 10 18 24
 1 100 100 1
 1 2 4 5
 1 2 3 4
 1 2 3 3
 4 4 4 5
 66 68 16 82
 1 2 3 2
 2 3 3 4
 100 100 100 100
 1 2 2 7
 3 14 36 53
 1 1 3 4

NO
 YES
 YES
 NO
 YES
 NO
 NO
 YES
 NO
 YES
 NO
 YES
 NO
 YES
 NO
 YES
 YES
 YES
 YES
 YES
 NO
 NO
 NO
 YES
 NO
 NO
 NO
 NO
 NO
 NO
 YES
 NO
 NO
 NO
 YES
 YES
 NO
 YES
 YES
 NO
 YES
 NO
 NO
 YES
 YES
 YES
 NO
 YES
 NO
 NO
 YES
 NO
 YES
 YES
 YES
 NO
 YES
 YES
 YES
 NO
 NO
 NO
 YES
 YES
 YES
 NO
 YES
 NO


	
	import java.io.BufferedOutputStream;
	import java.io.BufferedReader;
	import java.io.InputStreamReader;
	import java.io.PrintWriter;
	import java.util.*;

	
	public class e {
	
	public static class FastReader {
		BufferedReader br;
		StringTokenizer st;
		//it reads the data about the specified point and divide the data about it ,it is quite fast
		//than using direct 
	
		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
	
		String next() {
			while (st == null || !st.hasMoreTokens()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (Exception r) {
					r.printStackTrace();
				}
			}
			return st.nextToken();
		}
	
		int nextInt() {
			return Integer.parseInt(next());//converts string to integer
		}
	
		double nextDouble() {
			return Double.parseDouble(next());
		}
	
		long nextLong() {
			return Long.parseLong(next());
		}
	
		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (Exception r) {
				r.printStackTrace();
			}
			return str;
		}
	}
	static ArrayList<String>list1=new ArrayList<String>();
	static void combine(String instr, StringBuffer outstr, int index,int k)
	{
		if(outstr.length()==k)
		{
			list1.add(outstr.toString());return;
		}
		if(outstr.toString().length()==0)
		outstr.append(instr.charAt(index));
	    for (int i = 0; i < instr.length(); i++)
	    {
	        outstr.append(instr.charAt(i));
	       
	        combine(instr, outstr, i + 1,k);
	        outstr.deleteCharAt(outstr.length() - 1);
	    }
	   index++;
	} 
	static ArrayList<ArrayList<Integer>>l=new ArrayList<>();
	static void comb(int n,int k,int ind,ArrayList<Integer>list)
	{
		if(k==0)
		{
			l.add(new ArrayList<>(list));
	
			return;
		}
		
		
		for(int i=ind;i<=n;i++)
		{
			list.add(i);
			comb(n,k-1,ind+1,list);
			
			list.remove(list.size()-1);
			
		}
		
		
		
		
		
	
	}
	
	static class Pair implements Comparable<Pair>{
	    int x;int y;
	    Pair(int x,int y){
	        this.x=x;
	        this.y=y;
	      //  this.i=i;
	    }
		@Override
		public int compareTo(Pair o) {
			// TODO Auto-generated method stub
			return (o.x*y-o.y*x);
			
		}
	}
	
		
	
	public static PrintWriter out = new PrintWriter (new BufferedOutputStream(System.out));
	  static HashMap<Long, Pair> sort(HashMap<Long, Pair> hm) 
	    { 
	        // Create a list from elements of HashMap 
	        List<Map.Entry<Long, Pair> > list = 
	               new LinkedList<Map.Entry<Long, Pair> >(hm.entrySet()); 
	  
	        // Sort the list 
	        Collections.sort(list, new Comparator<Map.Entry<Long, Pair> >() { 
	            public int compare(Map.Entry<Long, Pair> o1,  
	                               Map.Entry<Long, Pair> o2) 
	            { 
	                return (o1.getValue().y)-(o2.getValue().y); 
	            } 
	        }); 
	          
	        // put data from sorted list to hashmap  
	        HashMap<Long, Pair> temp = new LinkedHashMap<Long, Pair>(); 
	        for (Map.Entry<Long, Pair> aa : list) { 
	            temp.put(aa.getKey(), aa.getValue()); 
	        } 
	        return temp; 
	    } 
	  static long ncr(long n, int k) 
	    { long m=(long)1e9+7;
	        long C[] = new long[k + 1]; 
	         
	        // nC0 is 1 
	        C[0] = 1;   
	       
	        for (int i = 1; i <= n; i++) 
	        { 
	            // Compute next row of pascal  
	            // triangle using the previous row 
	            for (int j = Math.min(i, k); j > 0; j--) 
	                C[j] = (C[j]%m + C[j-1]%m)%m; 
	        } 
	        return C[k]%m; 
	    } 
	  static long high(long n) 
	  { 
	        
	      long p = (long)(Math.log(n) /  
	                    Math.log(2L)); 
	      return (long)Math.pow(2L, p);  
	  }
	  static int findd(int a){
	        if (parent[a]!=a){
	            parent[a] = findd(parent[a]);
	        }
	        return parent[a];
	    }
	 static int parent[];
	 static ArrayList<Integer>list=new ArrayList<Integer>();
	 static HashMap<Integer,Integer>map;
	 static boolean find(int n,int f)
	 {
		 if(map.containsKey(n))
		 {	
			 if(map.get(n)>=f)
			 {
				 map.put(n, map.get(n)-f);
				 if(map.get(n)==0)
					 map.remove(n);
				 return true;
			 }
			 else
			 {
				 f-=map.get(n);
				 map.remove(n);
				 if(find(n/2,2*f))
					 return true;
				 else
					 return false;
			 }
			
		 }
		 else if(n>1)
		 {
			if(find(n/2,2*f))
				return true;
			else
				return false;
		 }
		 else
			 return false;
	
	 }
	 
		public static void main(String[] args) {
			// TODO Auto-generated method stub
	
		FastReader in=new FastReader();
		ArrayList<String>list=new ArrayList<String>();
		TreeSet<Character>set=new TreeSet<Character>();
      HashMap<Integer,Integer>map=new HashMap<Integer,Integer>();
     
    	int n=4;
    	int a[]=new int[n];int sum=0;
    	for(int i=0;i<n;i++)
    	{
    		a[i]=in.nextInt();sum+=a[i];
    	}
      
    	Arrays.sort(a);
    	if(a[3]==sum-a[3])
    	{
    		out.println("YES");out.flush();return;
    	}
      for(int i=1;i<n;i++)
      {
    	  if((a[0]+a[i])==(sum-a[0]-a[i]))
    	  {
    		  out.println("YES");out.flush();return;
    	  }
      }
      out.println("NO");out.close();
      
		}
		
	}	
		
		
		
	
