Java练习 SDUT-1588_圆的面积

圆的面积

Time Limit: 1000 ms Memory Limit: 32768 KiB

Problem Description

Give you the radius of a circle，caculate its area，PI=3.141592653。

Input

The first line of the input is a positive integer N,then follows N lines,each line is a real number represent the radius of the circle.

Output

Output contains N lines,for each line of the input you should output one line, Case K: S,and K(count from 1)represents the number of the circle and S is the area.Keep two digits after the decimal point.

Sample Input

3
1
2
3

Sample Output

Case 1: 3.14
Case 2: 12.57
Case 3: 28.27

注意圆周率的值。

import java.util.*;

public class Main
{
	static public void main(String[] args)
	{
		Scanner cin = new Scanner(System.in);
		int t,n;
		node a = new node();
		t = 0;
		n = cin.nextInt();
		while(++t<=n)
		{
			a.a = cin.nextDouble();
			System.out.printf("Case %d: ",t);
			System.out.printf("%.2f\n",a.GetSize());
		}
		cin.close();
	}
}

class node
{
	public double PI = 3.141592653;
	double a;
	double GetSize()
	{
		return a*a*PI;
	}
}