Skip to content
Related Articles

Related Articles

Program to calculate the area between two Concentric Circles
  • Last Updated : 14 Apr, 2021

Given two concentric circles with radius X and Y where (X > Y). Find the area between them. 
You are required to find the area of the green region as shown in the following image: 
 

Examples: 

Input : X = 2, Y = 1
Output : 9.42478

Input : X = 4, Y = 2
Output : 37.6991

Approach:
The area between the two given concentric circles can be calculated by subtracting the area of the inner circle from the area of the outer circle. Since X>Y. X is the radius of the outer circle.
Therefore, area between the two given concentric circles will be: 

π*X2 - π*Y2

Below is the implementation of the above approach:



C++




// C++ program to find area between the
// two given concentric circles
 
#include <bits/stdc++.h>
using namespace std;
 
// Function to find area between the
// two given concentric circles
double calculateArea(int x, int y)
{
    // Declare value of pi
    double pi = 3.1415926536;
 
    // Calculate area of outer circle
    double arx = pi * x * x;
 
    // Calculate area of inner circle
    double ary = pi * y * y;
 
    // Difference in areas
    return arx - ary;
}
 
// Driver Program
int main()
{
    int x = 2;
    int y = 1;
 
    cout << calculateArea(x, y);
 
    return 0;
}

Java




// Java program to find area between the
// two given concentric circles
import java.io.*;
 
class GFG
{
     
// Function to find area between the
// two given concentric circles
static double calculateArea(int x, int y)
{
    // Declare value of pi
    double pi = 3.1415926536;
 
    // Calculate area of outer circle
    double arx = pi * x * x;
 
    // Calculate area of inner circle
    double ary = pi * y * y;
 
    // Difference in areas
    return arx - ary;
}
 
// Driver code
public static void main (String[] args)
{
    int x = 2;
    int y = 1;
    System.out.println (calculateArea(x, y));
}
}
 
// This code is contributed by jit_t.

Python3




# Python3 program to find area between 
# the two given concentric circles
 
# Function to find area between the
# two given concentric circles
def calculateArea(x, y):
 
    # Declare value of pi
    pi = 3.1415926536
 
    # Calculate area of outer circle
    arx = pi * x * x
 
    # Calculate area of inner circle
    ary = pi * y * y
 
    # Difference in areas
    return arx - ary
 
# Driver Code
x = 2
y = 1
 
print(calculateArea(x, y))
 
# This code is contributed
# by shashank_sharma

C#




// C# program to find area between the
// two given concentric circles
using System;
 
class GFG
{
     
// Function to find area between the
// two given concentric circles
static double calculateArea(int x, int y)
{
    // Declare value of pi
    double pi = 3.1415926536;
 
    // Calculate area of outer circle
    double arx = pi * x * x;
 
    // Calculate area of inner circle
    double ary = pi * y * y;
 
    // Difference in areas
    return arx - ary;
}
 
// Driver code
public static void Main ()
{
    int x = 2;
    int y = 1;
    Console.WriteLine(calculateArea(x, y));
}
}
 
// This code is contributed by Code_Mech.

PHP




<?php
// PHP program to find area between the
// two given concentric circles
 
// Function to find area between the
// two given concentric circles
function calculateArea($x, $y)
{
    // Declare value of pi
    $pi = 3.1415926536;
 
    // Calculate area of outer circle
    $arx = $pi * $x * $x;
 
    // Calculate area of inner circle
    $ary = $pi * $y * $y;
 
    // Difference in areas
    return ($arx - $ary);
}
 
// Driver Code
$x = 2;
$y = 1;
 
echo calculateArea($x, $y);
 
// This code is contributed by akt_mit
?>

Javascript




<script>
 
// Javascript program to find area between
// the two given concentric circles
 
// Function to find
// nth concentric hexagon number
function calculateArea(x, y)
{
     
    // Declare value of pi
    var pi = 3.1415926536;
 
    // Calculate area of outer circle
    var arx = pi * x * x;
 
    // Calculate area of inner circle
    var ary = pi * y * y;
     
    // Difference in areas
    return arx - ary;
}
 
// Driver code
var x = 2;
var y = 1;
         
// Function call
document.write(calculateArea(x, y));
 
// This code is contributed by Ankita saini
 
</script>
Output: 
9.42478

 

Time Complexity: O(1)
 

Attention reader! Don’t stop learning now. Get hold of all the important mathematical concepts for competitive programming with the Essential Maths for CP Course at a student-friendly price. To complete your preparation from learning a language to DS Algo and many more,  please refer Complete Interview Preparation Course.

My Personal Notes arrow_drop_up
Recommended Articles
Page :