# Program to calculate the area between two Concentric Circles

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 = 1Output :9.42478Input :X = 4, Y = 2Output :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*X^{2}- π*Y^{2}

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; ` `} ` |

*chevron_right*

*filter_none*

## 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. ` |

*chevron_right*

*filter_none*

## Python 3

`# 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 ` |

*chevron_right*

*filter_none*

## 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. ` |

*chevron_right*

*filter_none*

## 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 ` `?> ` |

*chevron_right*

*filter_none*

**Output:**

9.42478

**Time Complexity:** O(1)

## Recommended Posts:

- Check if a given circle lies completely inside the ring formed by two concentric circles
- Program to calculate Area Of Octagon
- Program to calculate the area of Kite
- Program to calculate area and volume of a Tetrahedron
- Program to calculate area of a rhombus whose one side and diagonal are given
- Program to calculate area of an Circle inscribed in a Square
- Program to calculate the Surface Area of a Triangular Prism
- Program to calculate area and perimeter of a rhombus whose diagonals are given
- Program to calculate the Area and Perimeter of Incircle of an Equilateral Triangle
- Program to calculate area of inner circle which passes through center of outer circle and touches its circumference
- Calculate Stirling numbers which represents the number of ways to arrange r objects around n different circles
- Calculate Volume, Curved Surface Area and Total Surface Area Of Cylinder
- Calculate area of pentagon with given diagonal
- Calculate volume and surface area of Torus
- Ratio of the distance between the centers of the circles and the point of intersection of two transverse common tangents to the circles

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.