#include<stdio.h>
int main(){
  long a,v,b,w,t;
  scanf("%ld %ld",&a,&v);
  scanf("%ld %ld",&b,&w);
  scanf("%ld",&t);
  if (b>a) {
    if(b+w*t>a+v*t)printf("NO");
    else printf("YES");
  }else{
    if(b+w*t<a+v*t)printf("NO");
    else printf("YES");
  }
  return 0;
}