# Number of n digit numbers that do not contain 9

• Last Updated : 27 Apr, 2021

Given a number n, find how many n digit number can be formed that does not contain 9 as it’s digit.
Examples:

```Input : 1
Output : 8
Explanation :
Except 9, all numbers are possible

Input : 2
Output : 72
Explanation :
Except numbers from 90 - 99 and all
two digit numbers that does not end
with 9 are possible.```

Total numbers of n digit number that can be formed will be 9*10^(n-1) as except first position all digits can be filled with 10 numbers (0-9). If a digit 9 is eliminated from the list then total number of n digit number will be 8*9^(n-1).
Below is the implementation of above idea:

## C++

 `// CPP program to find number of n``// digit numbers that do not``// contain 9 as it's digit``#include ``using` `namespace` `std;` `// function to find number of``// n digit numbers possible``int` `totalNumber(``int` `n)``{``    ``return` `8*``pow``(9, n - 1);``}` `// driver function``int` `main()``{``    ``int` `n = 3;``    ``cout << totalNumber(n);``    ``return` `0;``}`

## Java

 `// Java program to find number of ``// n digit numbers that do not``// contain 9 as it's digit``import` `java.io.*;` `public` `class` `GFG``{``    ` `// function to find number of``// n digit numbers possible``static` `int` `totalNumber(``int` `n)``{``    ``return` `8` `* (``int``)Math.pow(``9``, n - ``1``);``}` `    ``// Driver Code``    ``static` `public` `void` `main (String[] args)``    ``{``        ``int` `n = ``3``;``        ``System.out.println(totalNumber(n));``        ` `    ``}``}` `// This code is contributed by vt_m.`

## Python3

 `# python program to find number of n``# digit numbers that do not``# contain 9 as it's digit` `# function to find number of``# n digit numbers possible``def` `totalNumber(n):``    ` `    ``return` `8` `*` `pow``(``9``, n ``-` `1``);`` ` `# driver function``n ``=` `3``print``(totalNumber(n))` `# This code is contributed by Sam007`

## C#

 `// C# program to find number of ``// n digit numbers that do not``// contain 9 as it's digit``using` `System;` `public` `class` `GFG``{``    ` `// function to find number of``// n digit numbers possible``static` `int` `totalNumber(``int` `n)``{``    ``return` `8 * (``int``)Math.Pow(9, n - 1);``}` `    ``// Driver Code``    ``static` `public` `void` `Main ()``    ``{``        ``int` `n = 3;``        ``Console.WriteLine(totalNumber(n));``        ` `    ``}``}` `// This code is contributed by vt_m.`

## php

 ``

## Javascript

 ``

Output:

`648`

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