Simple C program to calculate area of circle r1 and r2

C Program to calculate area of circle r1 and r2

#include<stdio.h>
int main()
{
float r1,r2,area;
printf("Enter r1 of circle:");
scanf("%f",&r1);
printf("Enter r2 of circle:");
scanf("%f",&r2);
area=3.146*(r1*r2);
printf("\nr1=%f",r1);
printf("\nr2=%f",r2);
printf("\n\narea=3.146*(%f*%f)",r1,r2);
printf("\n\nArea of circle=%f",area);
return 0;
}

The output of above program is: