View Code of Problem 104

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

int main(){
	double n,v1,v2,t;
	while(scanf("%lf %lf %lf %lf",&n,&v1,&v2,&t)!=EOF){
		if(v2>=v1) printf("NO\n");
		else{
			if(t>=n*1000/(v1-v2)) printf("%.2lf\n",n*1000/(v1-v2));
			else printf("NO\n");
		}
	}
}