Solution of URI 1002 :: Area of a Circle

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/**Bismillahir Rahmanir Rahim.**/

#include <stdio.h>
#define PI 3.14159

int main()
{
    double A, R;
    scanf("%lf", &R);
    A = PI * R * R;
    printf("A=%.4lf\n", A);
    return 0;
}

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