C. Meme Problem

链接

[http://codeforces.com/contest/1076/problem/C]

题意

a+b=d and a⋅b=d. 计算出a和b

分析

ab=a(d-a)=d

aa-ad+d=0; 先判断再直接求根公式

代码

#include<bits/stdc++.h>

using namespace std;

int main(){

	int t,d;

	cin>>t;

	while(t--){

		cin>>d;

		if(d*d-4*d<0) cout<<"N\n";

		else{

			cout<<"Y\n";

			double a=(d*1.0-sqrt(d*d-4*d))/2.0,b=(d*1.0+sqrt(d*d-4*d))/2.0;

			printf("%.9f %.9f\n",a,b);

		}

	}

	return 0;

}