View Code of Problem 104

#include <iostream>
#include <math.h>
using namespace std;

int main(){
    double n,v1,v2,t,time,s;
    while(scanf("%lf%lf%lf%lf",&n,&v1,&v2,&t)!=EOF){
        s = v1-v2;
        if(s*t<(n*1000))
            printf("NO\n");
        else
            printf("%.2lf\n",n*1000/s);
    }
    return 0;
}