#include<iostream>
#include<cstdio>
using namespace std;
int main() {
	pair<pair<int,int>,int> a,b;
	scanf("%d.%d.%d",&a.first.first,&a.first.second,&a.second);
	scanf("%d.%d.%d",&b.first.first,&b.first.second,&b.second);
	if(a<b)cout<<"NO"<<endl;
	else cout<<"YES"<<endl;
}