#include #define rep(i,n)for(long long i=0;i<(long long)(n);++i) #define all(a) a.begin(), a.end() using namespace std; typedef long long ll; typedef unsigned long long ull; typedef pair P; template inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; } const ll MOD=1e9+7; const ll INF=1e18; const int MAX=510000; const double pi=acos(-1); int dx[8] = {1,0,-1,0,1,1,-1,-1}; int dy[8] = {0,1,0,-1,-1,1,1,-1}; int main(){ cin.tie(0); ios::sync_with_stdio(false); int a,b,c,d,e,f; char i,j,k,l; cin >> a >> i >> b >> j >> c >> d >> k >> e >> l >> f; a=a*100+b*10+c; d=d*100+e*10+f; if(a>d)cout << "YES" << endl; else cout << "NO" << endl; return 0; }