# Check if a large number is divisible by 6 or not

Given a number, the task is to check if a number is divisible by 6 or not. The input number may be large and it may not be possible to store even if we use long long int.

Examples:

```Input  : n = 2112
Output : Yes

Input : n = 1124
Output : No

Input  : n = 363588395960667043875487
Output : No```

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Since input number may be very large, we cannot use n % 6 to check if a number is divisible by 8 or not, especially in languages like C/C++. The idea is based on following fact.

```A number is divisible by 6 it's divisible by 2 and 3.
a)  A number is divisible by 2 if its last digit is divisible by 2.
b)  A number is divisible by 3 if sum of digits is divisible by 3.
```

Below is the implementation based on above steps.

## C++

 `// C++ program to find if a number is divisible by ` `// 6 or not ` `#include ` `using` `namespace` `std; ` ` `  `// Function to find that number divisible by 6 or not ` `bool` `check(string str) ` `{ ` `    ``int` `n = str.length(); ` ` `  `    ``// Return false if number is not divisible by 2. ` `    ``if` `((str[n-1]-``'0'``)%2 != 0) ` `       ``return` `false``; ` ` `  `    ``// If we reach here, number is divisible by 2. ` `    ``// Now check for 3. ` ` `  `    ``// Compute sum of digits ` `    ``int` `digitSum = 0; ` `    ``for` `(``int` `i=0; i

## Java

 `// Java program to find if a number is ` `// divisible by 6 or not ` `class` `IsDivisible ` `{ ` `    ``// Function to find that number divisible by 6 or not ` `    ``static` `boolean` `check(String str) ` `    ``{ ` `        ``int` `n = str.length(); ` `      `  `        ``// Return false if number is not divisible by 2. ` `        ``if` `((str.charAt(n-``1``) -``'0'``)%``2` `!= ``0``) ` `           ``return` `false``; ` `      `  `        ``// If we reach here, number is divisible by 2. ` `        ``// Now check for 3. ` `      `  `        ``// Compute sum of digits ` `        ``int` `digitSum = ``0``; ` `        ``for` `(``int` `i=``0``; i

## Python3

 `# Python 3 program to find  ` `# if a number is divisible ` `# by 6 or not ` ` `  `# Function to find that number  ` `# is divisible by 6 or not ` `def` `check(st) : ` `    ``n ``=` `len``(st) ` `     `  `     `  `    ``# Return false if number ` `    ``# is not divisible by 2. ` `    ``if` `(((``int``)(st[n``-``1``])``%``2``) !``=` `0``) : ` `        ``return` `False` `  `  `    ``# If we reach here, number  ` `    ``# is divisible by 2. Now ` `    ``# check for 3. ` `  `  `    ``# Compute sum of digits ` `    ``digitSum ``=` `0` `    ``for` `i ``in` `range``(``0``, n) : ` `        ``digitSum ``=` `digitSum ``+` `(``int``)(st[i]) ` `  `  `    ``# Check if sum of digits ` `    ``# is divisible by 3 ` `    ``return` `(digitSum ``%` `3` `=``=` `0``) ` ` `  ` `  `# Driver code ` `st ``=` `"1332"` `if``(check(st)) : ` `    ``print``(``"Yes"``) ` `else` `: ` `    ``print``(``"No "``) ` `     `  `# This article is contributed by Nikita Tiwari. `

## C#

 `// C# program to find if a number is ` `// divisible by 6 or not ` `using` `System; ` ` `  `class` `GFG { ` `     `  `    ``// Function to find that number ` `    ``// divisible by 6 or not ` `    ``static` `bool` `check(String str) ` `    ``{ ` `        ``int` `n = str.Length; ` `     `  `        ``// Return false if number is ` `        ``// not divisible by 2. ` `        ``if` `((str[n-1] -``'0'``) % 2 != 0) ` `            ``return` `false``; ` `     `  `        ``// If we reach here, number is ` `        ``// divisible by 2. ` `        ``// Now check for 3. ` `     `  `        ``// Compute sum of digits ` `        ``int` `digitSum = 0; ` `        ``for` `(``int` `i = 0; i < n; i++) ` `            ``digitSum += (str[i] - ``'0'``); ` `     `  `        ``// Check if sum of digits is ` `        ``// divisible by 3 ` `        ``return` `(digitSum % 3 == 0); ` `    ``} ` `     `  `    ``// main function ` `    ``public` `static` `void` `Main ()  ` `    ``{ ` `        ``String str = ``"1332"``; ` `         `  `        ``if``(check(str)) ` `            ``Console.Write(``"Yes"``); ` `        ``else` `            ``Console.Write(``"No"``); ` `    ``} ` `} ` ` `  `// This code is contributed by parashar. `

## PHP

 ` `

Output:

```Yes
```

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