# Check if the given number is divisible by 71 or not

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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