# Largest Even and Odd N-digit numbers in Octal Number System

• Last Updated : 23 Feb, 2021

Given an integer N, the task is to find the largest even and odd N-digit numbers in Octal Number System.
Examples:

Input: N = 4
Output:
Even : 7776
Odd : 7777
Input: N = 2
Output:
Even : 76
Odd : 77

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Approach: To get the largest number, the digits of the number have to be maximum possible. Since in the octal number system, the maximum digit is ‘7’. So, generate ‘7’ (N – 1) times and then append ‘6’ for even and ‘7’ for odd in the end.
Below is the implementation of the above approach:

## C++

 `// C++ implementation of the approach``#include ``using` `namespace` `std;` `// Function to print the largest n-digit even``// and odd numbers in octal number system``void` `findNumbers(``int` `n)``{` `    ``// Append '7' (N - 1) times``    ``string ans = string(n - 1, ``'7'``);` `    ``// Append '6' for an even number``    ``string even = ans + ``'6'``;` `    ``// Append '7' for an odd number``    ``string odd = ans + ``'7'``;` `    ``cout << ``"Even : "` `<< even << endl;``    ``cout << ``"Odd : "` `<< odd << endl;``}` `// Driver code``int` `main()``{``    ``int` `n = 4;` `    ``findNumbers(n);` `    ``return` `0;``}`

## Java

 `// Java implementation of the approach``class` `GFG``{` `// Function to print the largest n-digit even``// and odd numbers in octal number system``static` `void` `findNumbers(``int` `n)``{` `    ``// Append '7' (N - 1) times``    ``String ans = ``""``;``    ``for` `(``int` `i = ``0``; i < n - ``1``; i++)``        ``ans += ``'7'``;` `    ``// Append '6' for an even number``    ``String even = ans + ``'6'``;` `    ``// Append '7' for an odd number``    ``String odd = ans + ``'7'``;` `    ``System.out.println(``"Even : "` `+ even);``    ``System.out.println(``"Odd : "` `+ odd);``}` `// Driver code``public` `static` `void` `main(String args[])``{``    ``int` `n = ``4``;` `    ``findNumbers(n);``}``}` `// This code is contributed by 29AjayKumar`

## Python3

 `# Python3 implementation of the approach ;` `# Function to print the largest n-digit even``# and odd numbers in octal number system``def` `findNumbers(N) :` `    ``# Append '7' (N - 1) times``    ``ans ``=` `'7'` `*` `(N ``-` `1``)` `    ``# Append '6' for an even number``    ``even ``=` `ans ``+` `'6'``;` `    ``# Append '7' for an odd number``    ``odd ``=` `ans ``+` `'7'``;` `    ``print``(``"Even : "``, even);``    ``print``(``"Odd : "``, odd );` `# Driver code``if` `__name__ ``=``=` `"__main__"` `:` `    ``n ``=` `4``;` `    ``findNumbers(n);` `# This code is contributed by AnkitRai01`

## C#

 `// C# implementation of the approach``using` `System;``    ` `class` `GFG``{` `// Function to print the largest n-digit even``// and odd numbers in octal number system``static` `void` `findNumbers(``int` `n)``{` `    ``// Append '7' (N - 1) times``    ``String ans = ``""``;``    ``for` `(``int` `i = 0; i < n - 1; i++)``        ``ans += ``'7'``;` `    ``// Append '6' for an even number``    ``String even = ans + ``'6'``;` `    ``// Append '7' for an odd number``    ``String odd = ans + ``'7'``;` `    ``Console.WriteLine(``"Even : "` `+ even);``    ``Console.WriteLine(``"Odd : "` `+ odd);``}` `// Driver code``public` `static` `void` `Main(String []args)``{``    ``int` `n = 4;` `    ``findNumbers(n);``}``}` `// This code is contributed by 29AjayKumar`

## Javascript

 ``
Output:
```Even : 7776
Odd : 7777```

Time Complexity: O(n)

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