Help me in solving CLB026 problem

help
, ,
1

My issue

How to find area of circle

My code

// Complete the code by updating the uderscores(__)
#include <stdio.h>

int main() {

  double pi = 3.14;
  double radius = 8.9;
  int area = pi * radius * radius;

  printf("%f",area);
  
}

Learning course: Programming and Problem solving using C
Problem Link: https://www.codechef.com/learn/course/ciet-programming-c/CIETPC05/problems/CLB026