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.*;
import java.math.BigInteger;
import java.util.*;
 
public class Solution {
    FastScanner in;
    PrintWriter out;
 
    class Item implements Comparable{
        int num;
        int count;
 
        public Item(int num, int count) {
            this.num = num;
            this.count = count;
        }
 
        public void increaseCount(){
            count++;
        }
 
        public int getCount() {
            return count;
        }
 
        public void setNum(int num) {
            this.num = num;
        }
 
        public int getNum() {
            return num;
        }
 
        @Override
        public int compareTo(Object o) {
            return count-((Item)o).count;
        }
    }
 
    void solve() {
       int arr[] = new int[4];
        int sum = 0, totalSum = 0;
        for (int i = 0; i < 4; i++) {
            arr[i] = in.nextInt();
            totalSum+=arr[i];
        }
 
        if (totalSum%2!=0)
            out.print("NO");
        else if (find(arr,totalSum/2,0)){
            out.print("YES");
        }else {
            out.print("NO");
        }
    }
 
    boolean find(int arr[], int sum, int currentIndex){
        if (currentIndex>=arr.length)
            return sum==0;
        if (sum==0)
            return true;
        boolean b1 = find(arr,sum-arr[currentIndex], currentIndex+1);
        boolean b2 = find(arr,sum, currentIndex+1);
        return b1 || b2;
    }
 
    void run() {
        try {
            in = new FastScanner(new File("Solution.in"));
            out = new PrintWriter(new File("Solution.out"));
 
            solve();
 
            out.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }
 
    void runIO() {
 
        in = new FastScanner(System.in);
        out = new PrintWriter(System.out);
 
        solve();
 
        out.close();
    }
 
    static void printArray(int arr[]){
        for (int i = 0; i < arr.length; i++) {
            System.out.print(arr[i]+", ");
        }
    }
 
    class FastScanner {
        BufferedReader br;
        StringTokenizer st;
 
        public FastScanner(File f) {
            try {
                br = new BufferedReader(new FileReader(f));
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            }
        }
 
        public FastScanner(InputStream f) {
            br = new BufferedReader(new InputStreamReader(f));
        }
 
        String next() {
            while (st == null || !st.hasMoreTokens()) {
                String s = null;
                try {
                    s = br.readLine();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (s == null)
                    return null;
                st = new StringTokenizer(s);
            }
            return st.nextToken();
        }
 
        boolean hasMoreTokens() {
            while (st == null || !st.hasMoreTokens()) {
                String s = null;
                try {
                    s = br.readLine();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (s == null)
                    return false;
                st = new StringTokenizer(s);
            }
            return true;
        }
 
        int nextInt() {
            return Integer.parseInt(next());
        }
 
        long nextLong() {
            return Long.parseLong(next());
        }
 
        double nextDouble() {
            return Double.parseDouble(next());
        }
 
        int[] nextIntArray(int n){
            int returnArray[] = new int[n];
            for (int i = 0; i < n; i++) {
                returnArray[i] = this.nextInt();
            }
            return returnArray;
        }
 
        String[] nextStringArray(int n){
            String returnArray[] = new String[n];
            for (int i = 0; i < n; i++) {
                returnArray[i] = this.next();
            }  
            return returnArray;
        }
 
        char[] nextCharArray(int n){
            char returnArray[] = new char[n];
            for (int i = 0; i < n; i++) {
                returnArray[i] = this.next().charAt(0);
            }
            return returnArray;
        }
 
        long[] nextLongArray(int n){
            long returnArray[] = new long[n];
            for (int i = 0; i < n; i++) {
                returnArray[i] = this.nextLong();
            }
            return returnArray;
        }
    }
 
    public static void main(String[] args) {
        new Solution().runIO();
    }
}