#include <iostream>
#include <math.h>
#include <algorithm>
#include <functional>
#include <vector>
#include <typeinfo>
#include <climits>
#include <ctype.h>
#include <string>
using namespace std;
#define INIT cin.tie(0); ios::sync_with_stdio(false);
#define FOR(i, a, n) for (int i = a; i < n; i++)
#define REP(i, n) for(int i = 0; i < n; i++)

int main()
{
    INIT;

    char d;
    int A[3], B[3];

    cin >> A[0] >> d >> A[1] >> d >> A[2];
    cin >> B[0] >> d >> B[1] >> d >> B[2];

    int a = 1000000 * A[0] + 1000 * A[1] + A[2];
    int b = 1000000 * B[0] + 1000 * B[1] + B[2];
    if(a > b or a == b) cout << "YES" << endl;
    else cout << "NO" << endl;

    return 0;
}