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10’s Complement of a decimal number
• Last Updated : 30 Apr, 2021

Given a decimal number N. The task is to find 10’s complement of the number N.
Example:

```Input : 25
Output : 10's complement is : 75

Input : 456
Output : 10's complement is : 544```

10’s complement of a decimal number can be found by adding 1 to the 9’s complement of that decimal number. It is just like 2s compliment in binary number representation.
Mathematically,

10’s complement = 9’s complement + 1

For example, let us take a decimal number 456, 9’s complement of this number will be 999-456 which will be 543. Now 10s compliment will be 543+1=544.
Therefore,

10’s complement = 10len – num

`Where, len = total number of digits in num.`

Below is the program to find 10’s complement of a given number:

## C++

 `// C++ program to find 10's complement` `#include``#include` `using` `namespace` `std;` `// Function to find 10's complement``int` `complement(``int` `num)``{``    ``int` `i,len=0,temp,comp;``    ` `    ``// Calculating total digits``    ``// in num``    ``temp = num;``    ``while``(1)``    ``{``        ``len++;``        ``num=num/10;``        ``if``(``abs``(num)==0)``            ``break``;       ``    ``}``    ` `    ``// restore num``    ``num = temp;``    ` `    ``// calculate 10's complement``    ``comp = ``pow``(10,len) - num;``    ` `    ``return` `comp;``}` `// Driver code``int` `main()``{``    ``cout<

## Java

 `// Java program to find 10's complement``import` `java.io.*;` `class` `GFG``{``// Function to find 10's complement``static` `int` `complement(``int` `num)``{``    ``int` `i, len = ``0``, temp, comp;``    ` `    ``// Calculating total``    ``// digits in num``    ``temp = num;``    ``while``(``true``)``    ``{``        ``len++;``        ``num = num / ``10``;``        ``if``(Math.abs(num) == ``0``)``            ``break``;``    ``}``    ` `    ``// restore num``    ``num = temp;``    ` `    ``// calculate 10's complement``    ``comp = (``int``)Math.pow(``10``,len) - num;``    ` `    ``return` `comp;``}` `// Driver code``public` `static` `void` `main (String[] args)``{``    ``System.out.println(complement(``25``));``    ` `    ``System.out.println(complement(``456``));``}``}` `// This code is contributed``// by chandan_jnu.`

## Python3

 `# Python3 program to find``# 10's complement``import` `math` `# Function to find 10's complement``def` `complement(num):``    ``i ``=` `0``;``    ``len` `=` `0``;``    ``comp ``=` `0``;``    ` `    ``# Calculating total``    ``# digits in num``    ``temp ``=` `num;``    ``while``(``1``):``        ``len` `+``=` `1``;``        ``num ``=` `int``(num ``/` `10``);``        ``if``(``abs``(num) ``=``=` `0``):``            ``break``;``    ` `    ``# restore num``    ``num ``=` `temp;``    ` `    ``# calculate 10's complement``    ``comp ``=` `math.``pow``(``10``, ``len``) ``-` `num;``    ` `    ``return` `int``(comp);` `# Driver code``print``(complement(``25``));``print``(complement(``456``));` `# This code is contributed by mits`

## C#

 `// C# program to find``// 10's complement``using` `System;` `class` `GFG``{``// Function to find 10's complement``static` `int` `complement(``int` `num)``{``    ``int` `len = 0, temp, comp;``    ` `    ``// Calculating total``    ``// digits in num``    ``temp = num;``    ``while``(``true``)``    ``{``        ``len++;``        ``num = num / 10;``        ``if``(Math.Abs(num) == 0)``            ``break``;``    ``}``    ` `    ``// restore num``    ``num = temp;``    ` `    ``// calculate 10's complement``    ``comp = (``int``)Math.Pow(10, len) - num;``    ` `    ``return` `comp;``}` `// Driver code``public` `static` `void` `Main ()``{``    ``Console.WriteLine(complement(25));``    ` `    ``Console.WriteLine(complement(456));``}``}` `// This code is contributed``// by chandan_jnu.`

## PHP

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## Javascript

 ``
Output:
```75
544```

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