acm--Mathematics--Xiang da oj 1088--cycloid

Xiang da OJ title address: Portal

Cycloid time limit: +Ms | Memory Limit:65536Kb

Description

A cycloid is the curve traced to a point in the rim of a circular wheel as the wheel rolls along a straight line. It is an example of a roulette, a curve generated by a curve rolling on another curve.

--from Wikipedia

Calculate the area of an arch of a cycloid generated by a circle of radius R.

Define PI as ACOs (-1.0).

Input

the first line of the input consists of a single integer K (1 <= k <=), denoting the number of test cases . Then K lines follow, each contains a real number R (0.0 < R < 1E3), indicating the radius of circle.

Output

for each test case, output a line containing one real number with exactly three digits after the decimal point, Indica Ting The area of an arch.

Sample Input

2

1.0

3.5

Sample Output

9.425

115.454

================================== 's Split Line =================================

The area of the arc that the circle passes through, this has a formula, the area that the cycloid leaves is equal to three times times the circle

#include <stdio.h> #include <iostream> #include <math.h>using namespace Std;int main () {    int n;    Double R;    scanf ("%d", &n);    while (n--) {       cin>>r;       Double X=3*acos ( -1.0) *r*r;       printf ("%.3f\n", x);    }}

acm--Mathematics--Xiang da oj 1088--cycloid