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.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.util.Scanner;
import java.lang.*;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import static java.util.Collections.list;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Random;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.TreeSet;
public class JavaApplication3 {
    
    
    static class FastReader 
    { 
        BufferedReader br; 
        StringTokenizer st; 
  
        public FastReader() 
        { 
            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; 
        } 
    } 
    
    static class BufPrint
    {
        final BufferedWriter bw;
        public BufPrint()
        {
            this.bw=new BufferedWriter(new OutputStreamWriter(System.out));
        }
        public void print(Object object)throws IOException
        {
            bw.append(""+object);
        }
        public void println(Object object)throws IOException
        {
            print(object);
            bw.append("\n");
        }
        public void close()throws IOException
        {
            bw.close();
        }
    }
    

        public static int GCD(int l,int r) {
        int gcd=1;
        for(int i = 1; i <= l && i <= r; ++i)
        {
            if(l % i==0 && r % i==0)
                gcd = i;
        }
    return gcd;
}
    
    public static void main(String[] args) throws IOException{
        
            FastReader sc=new FastReader(); 
            BufPrint bp=new BufPrint();
          
//                long t=sc.nextLong();
//                
//                for(int k=0;k<t;k++)
//                {
                    int[] a=new int[4];
                    
                    for(int i=0;i<4;i++)
                    {
                        a[i]=sc.nextInt();
                    }
                    Arrays.sort(a);
                    
                    int sum1=a[3]+a[0];
                    int sum2=a[2]+a[1];
                    if(sum1==sum2){
                        bp.println("YES");
                    }
                    else{
                        if(sum2+a[0]==a[3])
                        {
                           bp.println("YES");
                        }
                        else
                        {
                           bp.println("NO");
                        }
                        
                    }
                   
                    
                    
                    
//                }
                

                bp.close();
            
    }
    
}