#include<stdio.h>
#include<algorithm>
int main(){
	int a,b,c,d,e,f;
	scanf("%d.%d.%d",&a,&b,&c);
	scanf("%d.%d.%d",&d,&e,&f);
	if(d<a||(d==a&&e<b)||(d==a&&e==b&&f<=c))printf("YES\n");
	else printf("NO\n");
}