Uri Online Judge Solution 1002 Area of a Circle

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Uri Online Judge Solution 1002 Area of a Circle

#include <stdio.h>
 int main()
 {
     double A,R,r=3.14159;
     scanf("%lf",&R);
     A=r*R*R;
     printf("A=%.4lf\n",A);
     return 0;
 }