# Minimum number of elements to be removed so that pairwise consecutive elements are same

Given a string str. The task is to count the minimum number of elements to be removed so that pairwise consecutive elements are same

Examples:

Input : str = “11344”
Output: 1
Remove the digit 3 from 3rd place so that the string becomes 1144. Thus pairwise two consecutive elements are same. Hence answer is 1.

Input : str = “55553”
Output : 1
Remove the digit 3 from the 5th place so that the string becomes 5555. Thus pairwise two consecutive elements are same. Hence answer is 1.

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

Approach: Check if the current two consecutive elements are same or not. If yes then increment the index by 2 and keep checking till all the elements get traversed. Else increment the index by 1 and count by 1.

Below is the implementation of the above approach:

## C++

 `// C++ implementation of the above approach ` `#include ` `using` `namespace` `std; ` ` `  `// Function to count the minimum number of elements ` `// to remove from a number so that pairwise two ` `// consecutive digits are same. ` `int` `countConsecutive(string s) ` `{ ` ` `  `    ``// initialize counting variable ` `    ``int` `count = 0; ` ` `  `    ``for` `(``int` `i = 0; i < s.size(); i++) { ` ` `  `        ``// check if two consecutive digits are same ` `        ``if` `(s[i] == s[i + 1]) ` `            ``i++; ` `        ``else` `            ``count++; ` `    ``} ` ` `  `    ``return` `count; ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` `    ``string str = ``"44522255"``; ` `    ``cout << countConsecutive(str); ` `    ``return` `0; ` `} `

## Java

 `// Java implementation of the above approach ` ` `  `class` `GFG { ` ` `  `// Function to count the minimum number of elements ` `// to remove from a number so that pairwise two ` `// consecutive digits are same. ` `    ``static` `int` `countConsecutive(String s) { ` ` `  `        ``// initialize counting variable ` `        ``int` `count = ``0``; ` ` `  `        ``for` `(``int` `i = ``0``; i < s.length(); i++) { ` ` `  `            ``// check if two consecutive digits are same ` `            ``if` `(s.charAt(i) == s.charAt(i + ``1``)) { ` `                ``i++; ` `            ``} ``else` `{ ` `                ``count++; ` `            ``} ` `        ``} ` ` `  `        ``return` `count; ` `    ``} ` ` `  `// Driver code ` `    ``public` `static` `void` `main(String args[]) { ` `        ``String str = ``"44522255"``; ` `        ``System.out.println(countConsecutive(str)); ` ` `  `    ``} ` `} ` ` `  `// This code is contributed by PrinciRaj19992 `

## Python3

 `# Python 3 implementation of the above approach  ` ` `  `# Function to count the minimum number of  ` `# elements to remove from a number so that  ` `# pairwise two consecutive digits are same.  ` `def` `countConsecutive(s):  ` ` `  `    ``# initialize counting variable  ` `    ``count ``=` `-``1` ` `  `    ``for` `i ``in` `range``(``len``(s)``-``1``): ` ` `  `        ``# check if two consecutive  ` `        ``# digits are same  ` `        ``if``(i <``=` `len``(s)): ` `            ``if` `(s[i] ``is` `s[i ``+` `1``]): ` `                ``i ``+``=` `1` `            ``else``: ` `                ``count ``+``=` `1` `    ``return` `count  ` ` `  `# Driver code  ` `if` `__name__ ``=``=` `'__main__'``: ` `    ``str` `=` `"44522255"` `    ``print``(countConsecutive(``str``)) ` `     `  `# This code is contributed by PrinciRaj1992  `

## C#

 `// C# implementation of above approach  ` `using` `System; ` `public` `class` `GFG {  ` ` `  `    ``// Function to count the minimum number of elements  ` `    ``// to remove from a number so that pairwise two  ` `    ``// consecutive digits are same.  ` `    ``static` `int` `countConsecutive(String s) {  ` ` `  `        ``// initialize counting variable  ` `        ``int` `count = 0;  ` ` `  `        ``for` `(``int` `i = 0; i < s.Length; i++) {  ` ` `  `            ``// check if two consecutive digits are same  ` `            ``if` `(s[i] == s[i+1]) {  ` `                ``i++;  ` `            ``} ``else` `{  ` `                ``count++;  ` `            ``}  ` `        ``}  ` ` `  `        ``return` `count;  ` `    ``}  ` ` `  `// Driver code  ` `    ``public` `static` `void` `Main() {  ` `        ``String str = ``"44522255"``;  ` `        ``Console.WriteLine(countConsecutive(str));  ` ` `  `    ``}  ` `}  ` ` `  `// This code is contributed by 29AjayKumar `

## PHP

 ` `

Output:

```2
```

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