#include<stdio.h>
#include<math.h>
#include<stdlib.h>


int main(){
    int a, b, c, d, eq=0, eq2=0;
    scanf("%d %d %d %d", &a, &b, &c, &d);
    eq= c-b;
    eq2= a-d;
    if(eq <= eq2)
        printf("Yes\n");
    else
        printf("No\n");
    return 0;

}

	
