#include <iostream>
#include <string>
#include <algorithm>
#include <cstdio>

using namespace std;

int main()
{
    int a[3], b[3];
    scanf("%d.%d.%d", &a[0], &a[1], &a[2]);
    scanf("%d.%d.%d", &b[0], &b[1], &b[2]);
    
    for(int i=0; i<3; i++){
        if(a[i] < b[i]){
            cout << "NO" << endl;
            return 0;
        }
        else if(a[i] > b[i]){
            cout << "YES" << endl;
            return 0;
        }
    }
    cout << "YES" << endl;

    return 0;
}