View Code of Problem 104

#include<stdio.h>
#include <math.h>
void main()
{
	int n,v1,v2,t;
	while(scanf("%d %d %d %d",&n,&v1,&v2,&t)!=EOF)
	{
		double t1;
		if(n==0) printf("0.00\n");
		else 
		{
			if(v1<=v2) printf("NO\n");
			else 
		   {
		   	    t1=n*1000/(v1-v2);
		   	    if(t1>t)
		   	    {
		   	    	printf("NO\n");
				}
				else printf("%.2f\n",t1);	
		   }	
		}
	}
}