# Check if two numbers are co-prime or not

Two numbers A and B are said to be Co-Prime or mutually prime if the Greatest Common Divisor of them is 1. You have been given two numbers A and B, find if they are Co-prime or not.**Examples :**

Input : 2 3 Output : Co-Prime Input : 4 8 Output : Not Co-Prime

## C++

`// CPP program to check if two` `// numbers are co-prime or not` `#include<bits/stdc++.h>` `using` `namespace` `std;` `// function to check and print if` `// two numbers are co-prime or not` `void` `coprime(` `int` `a, ` `int` `b) {` ` ` ` ` `if` `( __gcd(a, b) == 1)` ` ` `cout << ` `"Co-Prime"` `<< endl;` ` ` `else` ` ` `cout << ` `"Not Co-Prime"` `<< endl; ` `}` `// driver code` `int` `main()` `{` ` ` `int` `a = 5, b = 6;` ` ` `coprime(a, b); ` ` ` `a = 8, b = 16;` ` ` `coprime(a, b); ` ` ` `return` `0;` `}` |

## Java

`// Java program to check if two` `// numbers are co-prime or not` `class` `GFG {` ` ` ` ` `// Recursive function to` ` ` `// return gcd of a and b` ` ` `static` `int` `__gcd(` `int` `a, ` `int` `b)` ` ` `{` ` ` `// Everything divides 0` ` ` `if` `(a == ` `0` `|| b == ` `0` `)` ` ` `return` `0` `;` ` ` ` ` `// base case` ` ` `if` `(a == b)` ` ` `return` `a;` ` ` ` ` `// a is greater` ` ` `if` `(a > b)` ` ` `return` `__gcd(a-b, b);` ` ` ` ` `return` `__gcd(a, b-a);` ` ` `}` ` ` ` ` `// function to check and print if` ` ` `// two numbers are co-prime or not` ` ` `static` `void` `coprime(` `int` `a, ` `int` `b) {` ` ` ` ` `if` `( __gcd(a, b) == ` `1` `)` ` ` `System.out.println(` `"Co-Prime"` `);` ` ` `else` ` ` `System.out.println(` `"Not Co-Prime"` `); ` ` ` `}` ` ` ` ` `//driver code` ` ` `public` `static` `void` `main (String[] args)` ` ` `{` ` ` `int` `a = ` `5` `, b = ` `6` `;` ` ` `coprime(a, b);` ` ` ` ` `a = ` `8` `; b = ` `16` `;` ` ` `coprime(a, b);` ` ` `}` `}` `// This code is contributed by Anant Agarwal.` |

## Python3

`# Python3 program to check if two` `# numbers are co-prime or not` `# Recursive function to` `# return gcd of a and b` `def` `__gcd(a, b):` ` ` `# Everything divides 0` ` ` `if` `(a ` `=` `=` `0` `or` `b ` `=` `=` `0` `): ` `return` `0` ` ` ` ` `# base case` ` ` `if` `(a ` `=` `=` `b): ` `return` `a` ` ` ` ` `# a is greater` ` ` `if` `(a > b):` ` ` `return` `__gcd(a ` `-` `b, b)` ` ` ` ` `return` `__gcd(a, b ` `-` `a)` `# Function to check and print if` `# two numbers are co-prime or not` `def` `coprime(a, b):` ` ` ` ` `if` `( __gcd(a, b) ` `=` `=` `1` `):` ` ` `print` `(` `"Co-Prime"` `)` ` ` `else` `:` ` ` `print` `(` `"Not Co-Prime"` `) ` `# Driver code` `a ` `=` `5` `; b ` `=` `6` `coprime(a, b)` `a ` `=` `8` `; b ` `=` `16` `coprime(a, b)` `# This code is contributed by Anant Agarwal` |

## C#

`// C# program to check if two` `// numbers are co-prime or not` `using` `System;` `class` `GFG {` ` ` `// Recursive function to` ` ` `// return gcd of a and b` ` ` `static` `int` `__gcd(` `int` `a, ` `int` `b)` ` ` `{` ` ` `// Everything divides 0` ` ` `if` `(a == 0 || b == 0)` ` ` `return` `0;` ` ` `// base case` ` ` `if` `(a == b)` ` ` `return` `a;` ` ` `// a is greater` ` ` `if` `(a > b)` ` ` `return` `__gcd(a - b, b);` ` ` `return` `__gcd(a, b - a);` ` ` `}` ` ` `// function to check and print if` ` ` `// two numbers are co-prime or not` ` ` `static` `void` `coprime(` `int` `a, ` `int` `b) {` ` ` `if` `(__gcd(a, b) == 1)` ` ` `Console.WriteLine(` `"Co-Prime"` `);` ` ` `else` ` ` `Console.WriteLine(` `"Not Co-Prime"` `);` ` ` `}` ` ` `// Driver code` ` ` `public` `static` `void` `Main()` ` ` `{` ` ` `int` `a = 5, b = 6;` ` ` `coprime(a, b);` ` ` `a = 8;` ` ` `b = 16;` ` ` `coprime(a, b);` ` ` `}` `}` `// This code is contributed by Anant Agarwal.` |

## PHP

`<?php` `// PHP program to check if two` `// numbers are co-prime or not` `// Recursive function to` `// return gcd of a and b` `function` `__gcd(` `$a` `, ` `$b` `)` ` ` `{` ` ` `// Everything divides 0` ` ` `if` `(` `$a` `== 0 || ` `$b` `== 0)` ` ` `return` `0;` ` ` `// base case` ` ` `if` `(` `$a` `== ` `$b` `)` ` ` `return` `$a` `;` ` ` `// a is greater` ` ` `if` `(` `$a` `> ` `$b` `)` ` ` `return` `__gcd(` `$a` `- ` `$b` `, ` `$b` `);` ` ` `return` `__gcd(` `$a` `, ` `$b` `- ` `$a` `);` ` ` `}` ` ` `// function to check and print if` ` ` `// two numbers are co-prime or not` `function` `coprime(` `$a` `, ` `$b` `)` `{` ` ` `if` `(__gcd(` `$a` `, ` `$b` `) == 1)` ` ` `echo` `"Co-Prime"` `,` `"\n"` `;` ` ` `else` ` ` `echo` `"Not Co-Prime"` `,` `"\n"` `;` `}` `// Driver Code` `$a` `= 5; ` `$b` `= 6;` `coprime(` `$a` `, ` `$b` `);` `$a` `= 8;` `$b` `= 16;` `coprime(` `$a` `, ` `$b` `);` `// This code is contributed by aj_36` `?>` |

## Javascript

`<script>` `// Javascript program to check if two` `// numbers are co-prime or not` `// Recursive function to` `// return gcd of a and b` `function` `__gcd(a, b)` `{` ` ` ` ` `// Everything divides 0` ` ` `if` `(a == 0 || b == 0)` ` ` `return` `0;` ` ` ` ` `// Base case` ` ` `if` `(a == b)` ` ` `return` `a;` ` ` ` ` `// a is greater` ` ` `if` `(a > b)` ` ` `return` `__gcd(a - b, b);` ` ` ` ` `return` `__gcd(a, b - a);` `}` `// Function to check and print if` `// two numbers are co-prime or not` `function` `coprime(a, b)` `{` ` ` `if` `(__gcd(a, b) == 1)` ` ` `document.write(` `"Co-Prime"` `+ ` `"<br>"` `);` ` ` `else` ` ` `document.write(` `"Not Co-Prime"` `); ` `}` `// Driver Code` `var` `a = 5, b = 6;` `coprime(a, b);` `a = 8; b = 16;` `coprime(a, b);` `// This code is contributed by Kirti` `</script>` |

**Output :**

Co-Prime Not Co-Prime

This article is contributed by **Dibyendu Roy Chaudhuri**. 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.

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