# Program to find the Area and Perimeter of a Semicircle

Given the radius of the semicircle as r, the task is to find out the Area and Perimeter of that semicircle.**Examples:**

Input:r = 10Output:Area = 157.00, Perimeter = 31.4Input:r = 25Output:Area =981.250000, Perimeter = 78.500000

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**Approach:**

In mathematics, a semicircle is a one-dimensional locus of points that forms half of a circle. The area of a semicircle is half the area of the circle from which it is made. Any diameter of a circle cuts it into two equal semicircles.

Area of Semi-Circle =^{1}⁄_{2}* π *r^{2}Perimeter of Semi-Circle = π *r

where “r” is the radius of the semicircle.

Below is the implementation of the above approach:

## C++

`// C++ program to find the` `// Area and Perimeter of a Semicircle` `#include <iostream>` `using` `namespace` `std;` `// Function for calculating the area` `float` `area(` `float` `r)` `{` ` ` `// Formula for finding the area` ` ` `return` `(0.5)*(3.14)*(r * r);` `}` `// Function for calculating the perimeter` `float` `perimeter(` `float` `r)` `{` ` ` `// Formula for finding the perimeter` ` ` `return` `(3.14)*(r);` `}` `// driver code` `int` `main()` `{` ` ` `// Get the radius` ` ` `int` `r = 10;` ` ` `// Find the area` ` ` `cout << ` `"The Area of Semicircle: "` ` ` `<< area(r) << endl;` ` ` `// Find the perimeter` ` ` `cout << ` `"The Perimeter of Semicircle: "` ` ` `<< perimeter(r) << endl;` ` ` `return` `0;` `}` |

## C

`// C program to find the` `// Area and Perimeter of a Semicircle` `#include <stdio.h>` `// Function for calculating the area` `float` `area(` `float` `r)` `{` ` ` `// Formula for finding the area` ` ` `return` `(0.5)*(3.14)*(r * r);` `}` `// Function for calculating the perimeter` `float` `perimeter(` `float` `r)` `{` ` ` `// Formula for finding the perimeter` ` ` `return` `(3.14)*(r);` `}` `// driver code` `int` `main()` `{` ` ` `// Get the radius` ` ` `float` `r = 10;` ` ` `// Find the area` ` ` `printf` `(` `"The Area of Semicircle: %f\n"` `,` ` ` `area(r));` ` ` `// Find the perimeter` ` ` `printf` `(` `"The Perimeter of Semicircle: %f\n"` `,` ` ` `perimeter(r));` ` ` `return` `0;` `}` |

## Java

`// Java program to find the` `// Area and Perimeter of a Semicircle` `import` `java.io.*;` `class` `GFG {` `// Function for calculating the area` `static` `float` `area(` `float` `r)` `{` ` ` `// Formula for finding the area` ` ` `return` `(` `float` `)((` `0.5` `)*(` `3.14` `)*(r * r));` `}` `// Function for calculating the perimeter` `static` `float` `perimeter(` `float` `r)` `{` ` ` `// Formula for finding the perimeter` ` ` `return` `(` `float` `)((` `3.14` `)*(r));` `}` `// driver code` ` ` `public` `static` `void` `main (String[] args) {` ` ` `// Get the radius` ` ` `float` `r = ` `10` `;` ` ` `// Find the area` ` ` `System.out.println(` `"The Area of Semicircle: "` `+` ` ` `area(r));` ` ` `// Find the perimeter` ` ` `System.out.println(` `"The Perimeter of Semicircle:"` `+` ` ` `+perimeter(r));` ` ` `}` `}` ` ` `// This code is contributed` `// by anuj_67..` |

## Python3

`# Python3 program to find the` `# Area and Perimeter of a Semicircle` `# Function for calculating the area` `def` `area(r):` ` ` ` ` `# Formula for finding the area` ` ` `return` `(` `0.5` `)` `*` `(` `3.14` `)` `*` `(r ` `*` `r)` `#Function for calculating the perimeter` `def` `perimeter(r):` ` ` ` ` `#Formula for finding the perimeter` ` ` `return` `(` `3.14` `)` `*` `(r)` `# driver code` `if` `__name__` `=` `=` `'__main__'` `:` ` ` `# Get the radius` ` ` `r ` `=` `10` ` ` `# Find the area` ` ` `print` `(` `"The Area of Semicircle: "` ` ` `,area(r))` ` ` `# Find the perimeter` ` ` `print` `(` `"The Perimeter of Semicircle: "` ` ` `,perimeter(r))` ` ` `# This code is contributed by` `# SURENDRA_GANGWAR` |

## C#

`// C# program to find the` `// Area and Perimeter of a Semicircle` `using` `System;` `class` `GFG {` `// Function for calculating the area` `static` `float` `area(` `float` `r)` `{` ` ` `// Formula for finding the area` ` ` `return` `(` `float` `)((0.5)*(3.14)*(r * r));` `}` `// Function for calculating the perimeter` `static` `float` `perimeter(` `float` `r)` `{` ` ` `// Formula for finding the perimeter` ` ` `return` `(` `float` `)((3.14)*(r));` `}` `// Driver Code` `public` `static` `void` `Main()` `{` ` ` `// Get the radius` ` ` `float` `r = 10;` ` ` ` ` `// Find the area` ` ` `Console.WriteLine(` `"The Area of Semicircle: "` `+` ` ` `area(r));` ` ` ` ` `// Find the perimeter` ` ` `Console.WriteLine(` `"The Perimeter of Semicircle:"` `+` ` ` `perimeter(r));` `}` `}` `// This code is contributed` `// by Akanksha Rai(Abby_akku)` |

## PHP

`<?php` `// PHP program to find the` `// Area and Perimeter of a Semicircle` `// Function for calculating the area` `function` `area(` `$r` `)` `{` ` ` `// Formula for finding the area` ` ` `return` `(0.5) * (3.14) * (` `$r` `* ` `$r` `);` `}` `// Function for calculating` `// the perimeter` `function` `perimeter(` `$r` `)` `{` ` ` `// Formula for finding` ` ` `// the perimeter` ` ` `return` `(3.14) * (` `$r` `);` `}` `// Driver code` `// Get the radius` `$r` `= 10;` `// Find the area` `echo` `"The Area of Semicircle: "` `,` ` ` `area(` `$r` `),` `"\n"` `;` `// Find the perimeter` `echo` `"The Perimeter of Semicircle: "` `,` ` ` `perimeter(` `$r` `),` `"\n"` `;` `// This code is contributed` `// by ANKITRAI1` `?>` |

## Javascript

`<script>` `// javascript program to find the` `// Area and Perimeter of a Semicircle` `// Function for calculating the area` ` ` `function` `area(r) {` ` ` `// Formula for finding the area` ` ` `return` `((0.5) * (3.14) * (r * r));` ` ` `}` ` ` `// Function for calculating the perimeter` ` ` `function` `perimeter(r) {` ` ` `// Formula for finding the perimeter` ` ` `return` `((3.14) * (r));` ` ` `}` ` ` `// driver code` ` ` ` ` `// Get the radius` ` ` `var` `r = 10;` ` ` `// Find the area` ` ` `document.write(` `"The Area of Semicircle: "` `+ area(r).toFixed(6)+` `"<br/>"` `);` ` ` `// Find the perimeter` ` ` `document.write(` `"The Perimeter of Semicircle: "` `+` ` ` `perimeter(r).toFixed(6)+` `"<br/>"` `);` `// This code contributed by gauravrajput1` `</script>` |

**Output:**

The Area of Semicircle: 157.000000 The Perimeter of Semicircle: 31.400000