# Check if two numbers are co-prime or not

• Difficulty Level : Basic
• Last Updated : 16 Feb, 2023

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``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``import` `java.io.*;``public` `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

 ` ``\$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

 ``

Output

```Co-Prime
Not Co-Prime
```

Time Complexity: O(log(max(a,b)))

Auxiliary Space: O(1)

This article is contributed by Dibyendu Roy Chaudhuri. If you like GeeksforGeeks and would like to contribute, you can also write an article using write.geeksforgeeks.org or mail your article to review-team@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.