#include <stdio.h>

int main(void)
{
int h = fgetc(stdin); 
int w = fgetc(stdin);
int n = fgetc(stdin);
int k = fgetc(stdin);
int loser = ((h * w) % n);
if (loser == 0)
    loser = n;

if (k == loser){
    printf("YES\n");
}else{
  printf("NO\n");
}

return 0;
}