# GCD of digits of a given number

Given a number n, find GCD of its digits.**Examples :**

Input : 345 Output : 1 GCD of 3, 4 and 5 is 1. Input : 2448 Output : 2 GCD of 2, 4, 4 and 8 is 2

We traverse the digits of number one by one using below loop

digit = n mod 10; n = n / 10;

While traversing digits, we keep track of current GCD and keep updating GCD by finding GCD of current digit with current GCD.

## C++

`// CPP program to find GCD of digits of a number` `#include<iostream>` `#include<algorithm>` `using` `namespace` `std;` `int` `digitGCD(` `int` `n)` `{` ` ` `int` `gcd = 0;` ` ` `while` `(n > 0)` ` ` `{ ` ` ` `gcd = __gcd(n%10, gcd);` ` ` `// If at point GCD becomes 1,` ` ` `// return it` ` ` `if` `(gcd == 1)` ` ` `return` `1;` ` ` `n = n/10;` ` ` `}` ` ` `return` `gcd;` `}` `// driver code` `int` `main()` `{` ` ` `long` `n = 2448;` ` ` `cout << digitGCD(n);` ` ` `return` `0;` `}` |

## Java

`// Java program to find GCD of digits of a number` `class` `GFG` `{` ` ` `// Recursive function to return gcd of a and b` ` ` `static` `int` `__gcd(` `int` `a, ` `int` `b)` ` ` `{` ` ` `return` `b == ` `0` `? a : __gcd(b, a % b);` ` ` ` ` `}` ` ` `static` `int` `digitGCD(` `int` `n)` ` ` `{` ` ` `int` `gcd = ` `0` `;` ` ` `while` `(n > ` `0` `)` ` ` `{ ` ` ` `gcd = __gcd(n % ` `10` `, gcd);` ` ` ` ` `// If at point GCD becomes 1,` ` ` `// return it` ` ` `if` `(gcd == ` `1` `)` ` ` `return` `1` `;` ` ` ` ` `n = n / ` `10` `;` ` ` `}` ` ` `return` `gcd;` ` ` `}` ` ` ` ` `// Driver code` ` ` `public` `static` `void` `main (String[] args)` ` ` `{` ` ` `int` `n = ` `2448` `;` ` ` `System.out.print(digitGCD(n));` ` ` `}` `}` `// This code is contributed by Anant Agarwal.` |

## Python3

`# Python program to find` `# GCD of digits of a number` `# Recursive function to return gcd of a and b` `def` `__gcd(a,b):` ` ` `return` `a ` `if` `(b` `=` `=` `0` `) ` `else` `__gcd(b, a ` `%` `b)` ` ` `def` `digitGCD(n):` ` ` `gcd ` `=` `0` ` ` `while` `(n > ` `0` `):` ` ` ` ` `gcd ` `=` `__gcd(n ` `%` `10` `, gcd)` ` ` ` ` `# If at point GCD becomes 1,` ` ` `# return it` ` ` `if` `(gcd ` `=` `=` `1` `):` ` ` `return` `1` ` ` ` ` `n ` `=` `n ` `/` `/` `10` ` ` ` ` `return` `gcd` `#Driver code` `n ` `=` `2448` `print` `(digitGCD(n))` `# This code is contributed` `# by Anant Agarwal.` |

## C#

`// C# program to find GCD of` `// digits of a number` `using` `System;` `class` `GFG {` ` ` ` ` `// Recursive function to return` ` ` `// gcd of a and b` ` ` `static` `int` `__gcd(` `int` `a, ` `int` `b)` ` ` `{` ` ` `return` `b == 0 ? a : __gcd(b, a % b);` ` ` ` ` `}` ` ` ` ` `static` `int` `digitGCD(` `int` `n)` ` ` `{` ` ` `int` `gcd = 0;` ` ` `while` `(n > 0)` ` ` `{ ` ` ` `gcd = __gcd(n % 10, gcd);` ` ` ` ` `// If at point GCD becomes 1,` ` ` `// return it` ` ` `if` `(gcd == 1)` ` ` `return` `1;` ` ` ` ` `n = n / 10;` ` ` `}` ` ` `return` `gcd;` ` ` `}` ` ` ` ` `// Driver code` ` ` `public` `static` `void` `Main ()` ` ` `{` ` ` `int` `n = 2448;` ` ` `Console.Write(digitGCD(n));` ` ` `}` `}` `// This code is contributed by Nitin Mittal.` |

## PHP

`<?php` `// PHP program to find GCD` `// of digits of a number` `// Recursive function to` `// return gcd of a and b` `function` `__gcd(` `$a` `,` `$b` `)` `{` ` ` `return` `$b` `== 0 ? ` `$a` `:` ` ` `__gcd(` `$b` `, ` `$a` `% ` `$b` `);` ` ` `}` ` ` `function` `digitGCD(` `$n` `)` `{` ` ` `$gcd` `= 0;` ` ` `while` `(` `$n` `> 0)` ` ` `{ ` ` ` `$gcd` `= __gcd(` `$n` `% 10, ` `$gcd` `);` ` ` `// If at point GCD` ` ` `// becomes 1, return it` ` ` `if` `(` `$gcd` `== 1)` ` ` `return` `1;` ` ` `$n` `= ` `$n` `/ 10;` ` ` `}` ` ` `return` `$gcd` `;` `}` `// Driver code` `$n` `= 2448;` `echo` `digitGCD(` `$n` `);` `// This code is contributed by Sam007` `?>` |

## Javascript

`<script>` `// javascript program to find GCD of digits of a number ` `// Recursive function to return gcd of a and b` ` ` `function` `__gcd(a, b)` ` ` `{` ` ` `return` `b == 0 ? a : __gcd(b, a % b);` ` ` `}` ` ` `function` `digitGCD(n)` ` ` `{` ` ` `var` `gcd = 0;` ` ` `while` `(n > 0)` ` ` `{` ` ` `gcd = __gcd(n % 10, gcd);` ` ` `// If at povar GCD becomes 1,` ` ` `// return it` ` ` `if` `(gcd == 1)` ` ` `return` `1;` ` ` `n = parseInt(n / 10);` ` ` `}` ` ` `return` `gcd;` ` ` `}` ` ` `// Driver code` ` ` `var` `n = 2448;` ` ` `document.write(digitGCD(n));` `// This code is contributed by aashish1995` `</script>` |

**Output :**

2

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