package seraphic;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.StringTokenizer;
import java.util.stream.Collectors;
import java.util.stream.Stream;



public class Seraphic {

    public static String readin()
    {
        String path = "src/seraphic/in.txt";
        Stream<String> lines;
        try {
            lines = Files.lines(Paths.get(path));
            String ret = lines.collect(Collectors.joining(System.lineSeparator()));
            lines.close();
            return(ret);
        } catch (IOException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return("Error");
    }
    static class LinkListElem
    {
        int data;
        LinkListElem Next;
        LinkListElem(int datain)
        {
            Next = null;
            data = datain;
        }
    }

    static class LinkList
    {
        LinkListElem head = null;
        LinkListElem end = null;
    }

    public static LinkList LinkListCreate()
    {
        LinkList l1 = new LinkList();
        l1.head = null;
        l1.end = null;
        return l1;
    }
    public static LinkList add(int data, LinkList L)
    {
        LinkListElem newElem = new LinkListElem(data);
        if(L.head==null)
        {
            L.head = newElem;
            L.end = newElem;
        }else
        {
            L.end.Next = newElem;
            L.end = newElem;
        }
        return L;
    }

    public static int ListLen(LinkList L)
    {
        LinkListElem curElem = L.head;
        int sum = 0;
        while(curElem != null)
        {
            sum += 1;
            curElem = curElem.Next;
        }
        return sum;
    }


    public static int ListIdx(LinkList L, int idx)
    {
        LinkListElem curElem = L.head;
        int i = 0;
        while(i < idx)
        {
            i+=1;
            curElem = curElem.Next;
        }
        return curElem.data;
    }

    public static boolean partitioncheck(LinkList L, int s1, int s2, int l1, int l2, int idx)
    {
        if(idx >= ListLen(L))
        {
            if((java.lang.Math.abs(l1-l2)<=1)&&(s1-s2==0))
            {
                return true;
            }else
            {
                return false;
            }
        }
        if(partitioncheck(L, s1+ListIdx(L, idx), s2, l1+1, l2, idx+1)||partitioncheck(L, s1, s2+ListIdx(L, idx), l1, l2+1, idx+1))
        {
            return true;
        }else
        {
            return false;
        }
    }
    public static void pcheck(LinkList L)
    {
        if(partitioncheck(L, 0, 0, 0, 0, 0))
        {
            System.out.println("YES");
        }else
        {
            System.out.println("NO");
        }
    }


    public static void main(String[] args)
    {
        LinkList L1 = LinkListCreate();
        String input = readin();
        StringTokenizer commarem = new StringTokenizer(input, " ");
        int c = 0;

        while (commarem.hasMoreElements())
        {
            c = Integer.parseInt((String) (commarem.nextElement()));
            add(c ,L1);
        }
        pcheck(L1);

    }

}