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Check if the given number is divisible by 71 or not
• Last Updated : 14 Apr, 2020

Given a number N, the task is to check whether the number is divisible by 71 or not.

Examples:

Input: N = 25411681
Output: yes
Explanation:
71 * 357911 = 25411681

Input: N = 5041
Output: yes
Explanation:
71 * 71 = 5041

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

Approach: The divisibility test of 71 is:

1. Extract the last digit.
2. Subtract 7 * last digit from the remaining number obtained after removing the last digit.
3. Repeat the above steps until a two-digit number, or zero, is obtained.
4. If the two-digit number is divisible by 71, or it is 0, then the original number is also divisible by 71.

For example:

```If N = 5041

Step 1:
N = 5041
Last digit = 1
Remaining number = 504
Subtracting 7 times last digit
Resultant number = 504 - 7*1 = 497

Step 2:
N = 497
Last digit = 7
Remaining number = 49
Subtracting 7 times last digit
Resultant number = 49 - 7*7 = 0

Step 3:
N = 0
Since N is a two-digit number,
and 0 is divisible by 71

Therefore N = 5041 is also divisible by 71
```

Below is the implementation of the above approach:

## C++

 `// C++ program to check whether a number``// is divisible by 71 or not``#include``#include`` ` `using` `namespace` `std;`` ` `// Function to check if the number is divisible by 71 or not ``bool` `isDivisible(``int` `n) ``{``    ``int` `d;``    ``// While there are at least two digits ``    ``while` `(n / 100) ``    ``{`` ` `        ``// Extracting the last ``        ``d = n % 10;`` ` `        ``// Truncating the number ``        ``n /= 10;`` ` `        ``// Subtracting seven times the last ``        ``// digit to the remaining number ``        ``n = ``abs``(n - (d * 7));``    ``}``    ``// Finally return if the two-digit``    ``// number is divisible by 71 or not``    ``return` `(n % 71 == 0) ;``}`` ` `// Driver Code ``int` `main() {``    ``int` `N = 5041;`` ` `    ``if` `(isDivisible(N)) ``        ``cout << ``"Yes"` `<< endl ;``    ``else``        ``cout << ``"No"` `<< endl ;``     ` `    ``return` `0;     ``} `` ` `// This code is contributed by ANKITKUMAR34`

## Java

 `// Java program to check whether a number``// is divisible by 71 or not``import` `java.util.*;`` ` `class` `GFG{`` ` `// Function to check if the number is divisible by 71 or not ``    ``static` `boolean` `isDivisible(``int` `n) ``    ``{``        ``int` `d;``        ``// While there are at least two digits ``        ``while` `((n / ``100``) <=``0``)``        ``{``     ` `            ``// Extracting the last ``            ``d = n % ``10``;``     ` `            ``// Truncating the number ``            ``n /= ``10``;``     ` `            ``// Subtracting seven times the last ``            ``// digit to the remaining number ``            ``n = Math.abs(n - (d * ``7``));``        ``}`` ` `        ``// Finally return if the two-digit``        ``// number is divisible by 71 or not``        ``return` `(n % ``71` `== ``0``) ;``    ``}``     ` `    ``// Driver Code ``    ``public` `static` `void` `main(String args[]){``        ``int` `N = ``5041``;``     ` `        ``if` `(isDivisible(N)) ``            ``System.out.println(``"Yes"``) ;``        ``else``            ``System.out.println(``"No"``);``    ``} ``}`` ` `// This code is contributed by AbhiThakur`

## Python 3

 `# Python program to check whether a number``# is divisible by 71 or not`` ` `# Function to check if the number is ``# divisible by 71 or not ``def` `isDivisible(n) : `` ` `    ``# While there are at least two digits ``    ``while` `n ``/``/` `100` `: `` ` `        ``# Extracting the last ``        ``d ``=` `n ``%` `10`` ` `        ``# Truncating the number ``        ``n ``/``/``=` `10`` ` `        ``# Subtracting seven times the last ``        ``# digit to the remaining number ``        ``n ``=` `abs``(n``-``(d ``*` `7``))`` ` `    ``# Finally return if the two-digit``    ``# number is divisible by 71 or not``    ``return` `(n ``%` `71` `=``=` `0``) `` ` `# Driver Code ``if` `__name__ ``=``=` `"__main__"` `: ``     ` `    ``N ``=` `5041`` ` `    ``if` `(isDivisible(N)) : ``        ``print``(``"Yes"``) ``    ``else` `: ``        ``print``(``"No"``) `

## C#

 `// C# program to check whether a number``// is divisible by 71 or not``using` `System; ``         ` `class` `GFG ``{ ``     ` `// Function to check if the number is divisible by 71 or not ``static` `bool` `isDivisible(``int` `n) ``{``    ``int` `d;``    ``// While there are at least two digits ``    ``while` `(n / 100 > 0) ``    ``{``     ` `        ``// Extracting the last ``        ``d = n % 10;``     ` `        ``// Truncating the number ``        ``n /= 10;``     ` `        ``// Subtracting fourteen times the last ``        ``// digit to the remaining number ``        ``n = Math.Abs(n - (d * 7));``    ``}``     ` `    ``// Finally return if the two-digit``    ``// number is divisible by 71 or not``    ``return` `(n % 71 == 0);``}``     ` `// Driver Code ``public` `static` `void` `Main() ``{ ``    ``int` `N = 5041;``     ` `    ``if` `(isDivisible(N)) ``        ``Console.WriteLine(``"Yes"``);``    ``else``        ``Console.WriteLine(``"No"``);``} ``} `` ` `// This code is contributed by mohit kumar 29. `
Output:
```Yes
```

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