# Minimum number of deletions so that no two consecutive are same

Given a string, find minimum number of deletions required so that there will be no two consecutive repeating characters in the string.

Examples:

```Input : AAABBB
Output : 4
Explanation : New string should be AB

Input : ABABABAB
Output : 0
Explanation : There are no consecutive repeating characters.
```

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

If there are n consecutive same characters delete n-1 out of those n characters.

## C++

 `// CPP code to count minimum deletions required ` `// so that there are no consecutive characters left ` `#include ` `using` `namespace` `std; ` ` `  `int` `countDeletions(string str) ` `{ ` `    ``int` `ans = 0; ` `    ``for` `(``int` `i = 0; i < str.length() - 1; i++)  ` `        `  `        ``// If two consecutive characters are  ` `        ``// the same, delete one of them. ` `        ``if` `(str[i] == str[i + 1])  ` `            ``ans++; ` `         `  `   ``return` `ans; ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` `    ``string str = ``"AAABBB"``; ` ` `  `    ``// Function call to print answer ` `    ``cout << countDeletions(str); ` ` `  `    ``return` `0; ` `} `

## Java

 `// Java code to count minimum deletions required ` `// so that there are no consecutive characters left ` `import` `java.util.*; ` ` `  `class` `GFG ` `{ ` `  ``static` `int` `countDeletions(String s) ` `  ``{ ` `    ``int` `ans = ``0``; ` `    ``char``[] str = s.toCharArray(); ` ` `  `    ``for` `(``int` `i = ``0``; i < str.length - ``1``; i++)  ` `         `  `        ``// If two consecutive characters are  ` `        ``// the same, delete one of them. ` `        ``if` `(str[i] == str[i + ``1``])  ` `            ``ans++;             ` `       `  `        ``return` `ans; ` `  ``} ` ` `  `    ``// Driver code ` `    ``public` `static` `void` `main(String[] args) ` `    ``{ ` `      ``String str = ``"AAABBB"``; ` `      ``// Function call to print answer  ` `     ``System.out.println(countDeletions(str)); ` `    ``} ` `} ` `/* This code is contributed by Mr. Somesh Awasthi */`

## Python

 `# Python code to count minimum deletions required ` `# so that there are no consecutive characters left\ ` ` `  `def` `countDeletions(string): ` `    ``ans ``=` `0` `    ``for` `i ``in` `range``(``len``(string) ``-` `1``): ` `         `  `        ``# If two consecutive characters are  ` `        ``# the same, delete one of them. ` `        ``if` `(string[i] ``=``=` `string[i ``+` `1``]):  ` `            ``ans ``+``=` `1` `         `  `    ``return` `ans ` `  `  `# Driver code ` `string ``=` `"AAABBB"` ` `  `# Function call to print answer ` `print` `countDeletions(string) ` ` `  `# This code is contributed by Sachin Bisht `

## C#

 `// C# Program to count minimum deletions ` `// required so that there are no ` `// consecutive characters left ` `using` `System; ` ` `  `class` `GFG ` `{ ` `     `  `// Function for counting deletions     ` `static` `int` `countDeletions(String s) ` `{ ` `    ``int` `ans = 0; ` `    ``char` `[]str = s.ToCharArray(); ` ` `  `    ``for` `(``int` `i = 0; i < str.Length - 1; i++)  ` `         `  `        ``// If two consecutive characters are  ` `        ``// the same, delete one of them. ` `        ``if` `(str[i] == str[i + 1])  ` `            ``ans++;          ` `     `  `        ``return` `ans; ` `} ` ` `  `    ``// Driver code ` `    ``public` `static` `void` `Main() ` `    ``{ ` `        ``String str = ``"AAABBB"``; ` `     `  `        ``// Function call to print answer  ` `        ``Console.Write(countDeletions(str)); ` `    ``} ` `} ` ` `  `// This code is contributed by Nitin Mittal. `

## PHP

 ` `

Output:

```4
```

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Improved By : nitin mittal

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