Program in C to find the area of circle

#include<stdio.h>

 int main()

{

float r,area;

printf("Enter radius of circle in cm : ");

scanf("%f",&r);

area=(22*r*r)/7;

printf("\n Area of circle : %f cm²",area);

return 0;

}

Output :

Enter radius of circle in cm : 3

Area of circle : 28.285715 cm²