#include<bits/stdc++.h>
#define ll long long int
#define pii pair<int,pair<int,int> >
#define F first
#define S second
using namespace std;
#define mod 1000000007

void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

///cout << "Case #"<<it<<": "<< res<< endl;

int main(){
    ios_base::sync_with_stdio(false);cin.tie(NULL);
    int t=1;///cin>>t;
    while(t--){
        int arr[4];
        for(int i=0;i<4;i++) cin>>arr[i];
        sort(arr,arr+4);
        if(arr[3]==arr[0]+arr[1]+arr[2]){
            cout<<"Yes"<<endl;
        }else if(arr[3]+arr[0]==arr[1]+arr[2]){
            cout<<"Yes"<<endl;
        }else cout<<"No"<<endl;

    }


}

#include <bits/stdc++.h>
using namespace std;
#define IOS              ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define print(a)         for(int i=0;i<(a.size());i++){cout<<a[i]<<"\n";}
#define sortt(a)         sort(a.begin(),a.end())
#define loop(i,a,b)      for(int i=0;i<n;i++)
#define int              long long
#define pb               push_back
#define mod              1000000007
#define PQ               priority_queue
#define F                first
#define S                second

void S_G_()
{
  string s;
  cin>>s;
  map<char,int>mp;
  for(int i=0;i<3;i++)
  {
    mp[s[i]]++;
  }
  if(mp[s[0]]==3)
  {
    cout<<"Won"<<endl;
  }
  else
  {
    cout<<"Lost"<<endl;
  }
}
signed main()
{
#ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
  IOS;
  int t=1;
  // cin>>t;
  while(t--)
  {
    S_G_();
  }
  cerr<<"time taken :"<<(float)clock()/CLOCKS_PER_SEC<<" secs"<<endl;
}