View Code of Problem 104

import java.util.Scanner;
import java.text.DecimalFormat;
public class Main{
	public static double n,a,b,v,t,k; 
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		DecimalFormat df=new DecimalFormat("######0.00"); 
		while(sc.hasNext()){
			n=sc.nextDouble();
			a=sc.nextDouble();
			b=sc.nextDouble();
			t=sc.nextDouble();
			v=a-b;
			k=n*1000/v;
			if(k<=t&&k>0) {
				System.out.println(df.format(k));
			}
			else {
				System.out.println("NO");
			}
		}
	}
}