#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define ll long long int #define LL unsigned long long #define pb push_back #define rep(i,n) for(int i=0;i<(n);i++) #define REP(i,n) for(int i=1;i<=(n);i++) using namespace std; int mx8[] = {0,0,1,-1,-1,1,-1,1}; int my8[] = {-1,1,0,0,-1,-1,1,1}; int mx4[] = {1,-1,0,0}; int my4[] = {0,0,-1,1}; const int MOD = 1000000007; int main() { int a,b,c,d; cin >> a >> b >> c >> d; if(ad) cout << "YES" << endl; else cout << "NO" << endl; }