#include <stdio.h>
int main(void){
  int a,b,c,d;
  int taka,ao;
  
  scanf("%d %d %d %d",&a,&b,&c,&d);
  
  taka=a-d;
  ao=c-b;
  if(taka<ao)
    puts("No");
  else 
    puts("Yes");
      
  return 0;
  }
