View Code of Problem 104

#include<bits/stdc++.h>
using namespace std;
int main(){
	double n,v1,v2,s;
	while(scanf("%lf%lf%lf%lf",&n,&v1,&v2,&s)!=EOF){
		if(v2>=v1)cout<<"NO"<<endl;
		else{
			double time = n*1000/(v1-v2);
			if(time > s)cout<<"NO"<<endl;
			else{
				printf("%.2lf\n",time);
			}
		}
	}
	
	
	
	
	
	return 0;
}