#include<stdio.h>
int main()
{
    int a,b,c,d,ans1,ans2;
    scanf("%d %d %d %d",&a,&b,&c,&d);
   ans1=c-b;
   ans2=a-d;
   if(ans1>ans2 || ans2==0)
    printf("No\n");

   else
    printf("Yes\n");

}
