LightOJ Problem:1022 (circle in square)

LightOJ Problem :1022

Circle in Squqre

Problem link:
 http://lightoj.com/login_main.php?url=volume_showproblem.php?problem=1022

solution:

#include<stdio.h>

#include<math.h>

#define pi 2*acos(0.0)

int main()

{

    int i,T;

    scanf("%d",&T);

    double radius;

    for(i=1; i<=T; i++)

    {

        scanf("%lf",&radius);

       double width=(2*radius);

        double area=(width*width);

        double circle=(pi*radius*radius);

        double blue=(area-circle);

        printf("Case %d: %.2lf\n",i,blue);

    }

    return 0;

}

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