View Code of Problem 104

#include<stdio.h>
int main() {
	int n,v1,v2,t;
	double time; 
	while(scanf("%d %d %d %d",&n,&v1,&v2,&t)!=EOF) {
		if(v1<v2)
			printf("N0\n");
		else {
		        n*=1000;
			 time=(double) n/(v1-v2);
			if(time<=t)
				printf("%.2lf\n",time);
			else
				printf("N0\n");
		}
	}
	return 0;
}