#include<bits/stdc++.h>
using namespace std;

const long long INF = 1LL << 60;
#define MOD 1000000007;

typedef long long ll;

#define writeln(n) cout<<n<<endl;

typedef pair<float, float> P;

typedef pair<string, int> Psi;

vector<int> a(3);
vector<int> b(3);
int main() {

;

	scanf("%d.%d.%d",&a[0],&a[1],&a[2]);
	scanf("%d.%d.%d",&b[0],&b[1],&b[2]);

	if(b<a){
		writeln("YES");
	}else {
		writeln("NO");
	}


}