# Absolute difference between the first X and last X Digits of N

Given two integers N and X. The task is to print the absolute difference between the first X and last X digits in N. Considering the number of digits is atleast 2*x.

Examples:

```Input: N = 21546, X = 2
Output: 25
The first two digit in 21546 is 21.
The last two digit in 21546 is 46.
The absolute difference of 21 and 46 is 25.

Input: N = 351684617, X = 3
Output: 266
```

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

Simple Approach:

• Store the last x digits of the number in last.
• Find the number of digits in the number.
• Remove all the digits except the first x.
• Store the first x integers of the number in first.

Below is the implementation of the above approach:

## C++

 `// C++ implementation of the above approach ` `#include ` `using` `namespace` `std; ` ` `  `// Function to find the ` `// number of digits in the integer ` `long` `long` `digitsCount(``long` `long` `n) ` `{ ` `    ``int` `len = 0; ` `    ``while` `(n > 0) { ` `        ``len++; ` `        ``n /= 10; ` `    ``} ` `    ``return` `len; ` `} ` ` `  `// Function to find the absolute difference ` `long` `long` `absoluteFirstLast(``long` `long` `n, ``int` `x) ` `{ ` `    ``// Store the last x digits in last ` `    ``int` `i = 0, mod = 1; ` `    ``while` `(i < x) { ` `        ``mod *= 10; ` `        ``i++; ` `    ``} ` `    ``int` `last = n % mod; ` ` `  `    ``// Count the no. of digits in N ` `    ``long` `long` `len = digitsCount(n); ` ` `  `    ``// Remove the digits except the first x ` `    ``while` `(len != x) { ` `        ``n /= 10; ` `        ``len--; ` `    ``} ` ` `  `    ``// Store the first x digits in first ` `    ``int` `first = n; ` ` `  `    ``// Return the absolute difference between ` `    ``// the first and last ` `    ``return` `abs``(first - last); ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` `    ``long` `long` `n = 21546, x = 2; ` `    ``cout << absoluteFirstLast(n, x); ` ` `  `    ``return` `0; ` `} `

## Java

 `// Java implementation of the above approach ` `import` `java.util.*; ` ` `  `class` `GFG ` `{ ` ` `  `// Function to find the ` `// number of digits in the integer ` `static` `int` `digitsCount(``int` `n) ` `{ ` `    ``int` `len = ``0``; ` `    ``while` `(n > ``0``)  ` `    ``{ ` `        ``len++; ` `        ``n /= ``10``; ` `    ``} ` `    ``return` `len; ` `} ` ` `  `// Function to find the absolute difference ` `static` `int` `absoluteFirstLast(``int` `n, ``int` `x) ` `{ ` `    ``// Store the last x digits in last ` `    ``int` `i = ``0``, mod = ``1``; ` `    ``while` `(i < x)  ` `    ``{ ` `        ``mod *= ``10``; ` `        ``i++; ` `    ``} ` `    ``int` `last = n % mod; ` ` `  `    ``// Count the no. of digits in N ` `    ``int` `len = digitsCount(n); ` ` `  `    ``// Remove the digits except the first x ` `    ``while` `(len != x) ` `    ``{ ` `        ``n /= ``10``; ` `        ``len--; ` `    ``} ` ` `  `    ``// Store the first x digits in first ` `    ``int` `first = n; ` ` `  `    ``// Return the absolute difference between ` `    ``// the first and last ` `    ``return` `Math.abs(first - last); ` `} ` ` `  `// Driver code ` `public` `static` `void` `main(String args[]) ` `{ ` `    ``int` `n = ``21546``, x = ``2``; ` `    ``System.out.println(absoluteFirstLast(n, x)); ` `} ` `} ` ` `  `// This code is contributed by ` `// Surendra_Gangwar `

## Python3

 `# Python3 implementation of the above approach  ` ` `  `# Function to find the  ` `# number of digits in the integer  ` `def` `digitsCount(n) : ` `    ``length ``=` `0``;  ` `    ``while` `(n > ``0``) :  ` `        ``length ``+``=` `1``;  ` `        ``n ``/``/``=` `10``;  ` `         `  `    ``return` `length;  ` ` `  ` `  `# Function to find the absolute difference  ` `def` `absoluteFirstLast(n, x) : ` `     `  `    ``# Store the last x digits in last  ` `    ``i ``=` `0` `; ` `    ``mod ``=` `1``; ` `    ``while` `(i < x) : ` `        ``mod ``*``=` `10``; ` `        ``i ``+``=` `1``;  ` `     `  `    ``last ``=` `n ``%` `mod; ` `     `  `    ``# Count the no. of digits in N ` `    ``length ``=` `digitsCount(n);  ` `     `  `    ``# Remove the digits except the first x ` `    ``while` `(length !``=` `x) : ` `        ``n ``/``/``=` `10``; ` `        ``length ``-``=` `1``;  ` `     `  `    ``# Store the first x digits in first  ` `    ``first ``=` `n;  ` `     `  `    ``# Return the absolute difference between ` `    ``# the first and last  ` `    ``return` `abs``(first ``-` `last);  ` ` `  `# Driver code  ` `if` `__name__ ``=``=` `"__main__"` `:  ` `     `  `    ``n ``=` `21546` `; ` `    ``x ``=` `2``;  ` `    ``print``(absoluteFirstLast(n, x));  ` `     `  `# This code is contributed by Ryuga `

## C#

 `// C# implementation of the approach  ` `using` `System; ` ` `  `class` `GFG  ` `{  ` ` `  `// Function to find the  ` `// number of digits in the integer  ` `static` `int` `digitsCount(``int` `n)  ` `{  ` `    ``int` `len = 0;  ` `    ``while` `(n > 0)  ` `    ``{  ` `        ``len++;  ` `        ``n /= 10;  ` `    ``}  ` `    ``return` `len;  ` `}  ` ` `  `// Function to find the absolute difference  ` `static` `int` `absoluteFirstLast(``int` `n, ``int` `x)  ` `{  ` `    ``// Store the last x digits in last  ` `    ``int` `i = 0, mod = 1;  ` `    ``while` `(i < x)  ` `    ``{  ` `        ``mod *= 10;  ` `        ``i++;  ` `    ``}  ` `    ``int` `last = n % mod;  ` ` `  `    ``// Count the no. of digits in N  ` `    ``int` `len = digitsCount(n);  ` ` `  `    ``// Remove the digits except the first x  ` `    ``while` `(len != x)  ` `    ``{  ` `        ``n /= 10;  ` `        ``len--;  ` `    ``}  ` ` `  `    ``// Store the first x digits in first  ` `    ``int` `first = n;  ` ` `  `    ``// Return the absolute difference between  ` `    ``// the first and last  ` `    ``return` `Math.Abs(first - last);  ` `}  ` ` `  `// Driver code  ` `public` `static` `void` `Main(String []args)  ` `{  ` `    ``int` `n = 21546, x = 2;  ` `    ``Console.Write(absoluteFirstLast(n, x));  ` `}  ` `}  ` ` `  `// This code has been contributed by 29AjayKumar `

## PHP

 ` 0)  ` `    ``{ ` `        ``\$len``++; ` `        ``\$n` `= (int)(``\$n` `/ 10); ` `    ``} ` `    ``return` `\$len``; ` `} ` ` `  `// Function to find the absolute difference ` `function` `absoluteFirstLast(``\$n``, ``\$x``) ` `{ ` `    ``// Store the last x digits in last ` `    ``\$i` `= 0; ` `    ``\$mod` `= 1; ` `    ``while` `(``\$i` `< ``\$x``) ` `    ``{ ` `        ``\$mod` `*= 10; ` `        ``\$i``++; ` `    ``} ` `    ``\$last` `= ``\$n` `% ``\$mod``; ` ` `  `    ``// Count the no. of digits in N ` `    ``\$len` `= digitsCount(``\$n``); ` ` `  `    ``// Remove the digits except the first x ` `    ``while` `(``\$len` `!= ``\$x``)  ` `    ``{ ` `        ``\$n` `= (int)(``\$n` `/ 10); ` `        ``\$len``--; ` `    ``} ` ` `  `    ``// Store the first x digits in first ` `    ``\$first` `= ``\$n``; ` ` `  `    ``// Return the absolute difference  ` `    ``// between the first and last ` `    ``return` `abs``(``\$first` `- ``\$last``); ` `} ` ` `  `// Driver code ` `\$n` `= 21546; ` `\$x` `= 2; ` `echo` `absoluteFirstLast(``\$n``, ``\$x``); ` ` `  `// This code is contributed by mits ` `?> `

Output:

```25
```

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