Program to find area of a circle

Try it on GfG Practice

Given the radius r. Find the area of a circle. The area of the circle should be correct up to 5 decimal places.

Examples:

Input: r = 5
Output: 78.53982
Explanation: As area = PI * r * r = 3.14159265358979323846 * 5 * 5 = 78.53982, as we only keep 5 digits after decimal.

Input: r = 2
Output: 12.56637
Explanation: As area = PI * r * r = 3.14159265358979323846 * 2 * 2 = 12.56637, as we only keep 5 digits after decimal.

The area of a circle can be calculated using the formula: area = PI * r * r

#include <iostream> #include <cmath> #include <iomanip> using namespace std; float findArea(float r) {  return (M_PI * r * r); } int main() {  float r = 5, area;  area = findArea(r);  cout << fixed << setprecision(5) << area;  return 0; } 

#include <stdio.h> #include <math.h> #define PI 3.14159265358979323846 float findArea(float r) {  return (PI * r * r); } int main() {  float r = 5, area;  area = findArea(r);  printf("%.5f\n", area);  return 0; } 

import java.lang.Math; class GfG {  static float findArea(float r) {  return (float)(Math.PI * r * r);  }  public static void main(String[] args) {  float r = 5;  float area = findArea(r);  System.out.printf("%.5f%n",area);  } } 

import math def findArea(r): return math.pi * r * r if __name__ == "__main__": r = 5 area = findArea(r) print(f"{area:.5f}") 

using System; class GfG {  static float FindArea(float r) {  return (float)(Math.PI * r * r);  }  static void Main() {  float r = 5;  float area = FindArea(r);  Console.WriteLine("{0:F5}",area);  } } 

function findArea(r) {  return Math.PI * r * r; } //Driver Code let r = 5; let area = findArea(r); console.log(area.toFixed(5)); 

78.53982

Time Complexity: O(1)
Auxiliary Space: O(1), since no extra space has been taken.