# Check if a string has m consecutive 1’s or 0’s

Given a binary string and a number m, the task is to check if the string has m consecutive 1’s or 0’s

Examples:

Input : str = “001001”, m = 2
Output : YES

Input : str = “1000000001”, m = 10
Output : NO

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

The approach is to count the consecutive 1’s or 0’s by traversing in the binary string. While traversing in the binary string, keep a count of the number of 1’s or 0’s appearing consecutively. If there are M consecutive 1’s or 0’s, return True else return False.

Given below is the implementation of the above approach:

## C++

 `// Program to check if the binary string  ` `// contains m consecutive 1's or 0's ` `#include ` `#include ` `using` `namespace` `std; ` ` `  `// Function that checks if ` `// the binary string contains m ` `// consecutive 1's or 0's ` `bool` `check(string s, ``int` `m) ` `{ ` `    ``// length of binary string ` `    ``int` `l = s.length(); ` ` `  `    ``// counts zeros ` `    ``int` `c1 = 0; ` ` `  `    ``// counts 1's ` `    ``int` `c2 = 0; ` ` `  `    ``for` `(``int` `i = 0; i < l; i++) { ` ` `  `        ``if` `(s[i] == ``'0'``) { ` `            ``c2 = 0; ` `            `  `           ``// count consecutive 0's ` `            ``c1++;  ` `        ``} ` `        ``else` `{ ` `            ``c1 = 0; ` ` `  `            ``// count consecutive 1's ` `            ``c2++;  ` `        ``} ` `        ``if` `(c1 == m || c2 == m) ` `            ``return` `true``; ` `    ``} ` `    ``return` `false``; ` `} ` ` `  `// Drivers Code ` `int` `main() ` `{ ` `    ``string s = ``"001001"``; ` `    ``int` `m = 2; ` ` `  `    ``// function call ` `    ``if` `(check(s, m)) ` `        ``cout << ``"YES"``; ` `    ``else` `        ``cout << ``"NO"``; ` ` `  `    ``return` `0; ` `} `

## Java

 `// Program to check if the  ` `// binary string contains  ` `// m consecutive 1's or 0's ` `import` `java.io.*; ` ` `  `class` `GFG  ` `{ ` ` `  `// Function that checks if ` `// the binary string contains m ` `// consecutive 1's or 0's ` `static` `boolean` `check(String s,  ` `                     ``int` `m) ` `{ ` `    ``// length of binary string ` `    ``int` `l = s.length(); ` ` `  `    ``// counts zeros ` `    ``int` `c1 = ``0``; ` ` `  `    ``// counts 1's ` `    ``int` `c2 = ``0``; ` ` `  `    ``for` `(``int` `i = ``0``; i < l; i++) ` `    ``{ ` ` `  `        ``if` `(s.charAt(i) == ``'0'``)  ` `        ``{ ` `            ``c2 = ``0``; ` `             `  `        ``// count consecutive 0's ` `            ``c1++;  ` `        ``} ` `        ``else`  `        ``{ ` `            ``c1 = ``0``; ` ` `  `            ``// count consecutive 1's ` `            ``c2++;  ` `        ``} ` `        ``if` `(c1 == m || c2 == m) ` `            ``return` `true``; ` `    ``} ` `    ``return` `false``; ` `} ` ` `  `// Drivers Code ` ` `  `public` `static` `void` `main (String[] args)  ` `{ ` `    ``String s = ``"001001"``; ` `    ``int` `m = ``2``; ` `     `  `    ``// function call ` `    ``if` `(check(s, m)) ` `        ``System.out.println( ``"YES"``); ` `    ``else` `        ``System.out.println( ``"NO"``); ` `} ` `} ` ` `  `// This code is contributed by anuj_67. `

## Python 3

 `# Program to check if the binary string  ` `# contains m consecutive 1's or 0's ` ` `  `# Function that checks if ` `# the binary string contains m ` `# consecutive 1's or 0's ` `def` `check(s, m): ` ` `  `    ``# length of binary string ` `    ``l ``=` `len``(s); ` ` `  `    ``# counts zeros ` `    ``c1 ``=` `0``; ` ` `  `    ``# counts 1's ` `    ``c2 ``=` `0``; ` ` `  `    ``for` `i ``in` `range``(``0``, l ``-` `1``):  ` ` `  `        ``if` `(s[i] ``=``=` `'0'``):  ` `            ``c2 ``=` `0``; ` `             `  `        ``# count consecutive 0's ` `            ``c1 ``=` `c1 ``+` `1``;  ` `         `  `        ``else` `: ` `            ``c1 ``=` `0``; ` ` `  `            ``# count consecutive 1's ` `            ``c2 ``=` `c2 ``+` `1``;  ` `         `  `        ``if` `(c1 ``=``=` `m ``or` `c2 ``=``=` `m): ` `            ``return` `True``; ` `     `  `    ``return` `False``; ` ` `  `# Driver Code ` `s ``=` `"001001"``; ` `m ``=` `2``; ` ` `  `# function call ` `if` `(check(s, m)): ` `    ``print``(``"YES"``); ` `else` `: ` `    ``print``(``"NO"``); ` ` `  `# This code is contributed  ` `# by Shivi_Agggarwal `

## C#

 `// Program to check if the  ` `// binary string contains  ` `// m consecutive 1's or 0's ` `using` `System; ` ` `  `class` `GFG  ` `{ ` ` `  `// Function that checks if ` `// the binary string contains  ` `// m consecutive 1's or 0's ` `static` `bool` `check(``string` `s,  ` `                  ``int` `m) ` `{ ` `    ``// length of  ` `    ``// binary string ` `    ``int` `l = s.Length; ` ` `  `    ``// counts zeros ` `    ``int` `c1 = 0; ` ` `  `    ``// counts 1's ` `    ``int` `c2 = 0; ` ` `  `    ``for` `(``int` `i = 0; i < l; i++) ` `    ``{ ` ` `  `        ``if` `(s[i] == ``'0'``)  ` `        ``{ ` `            ``c2 = 0; ` `             `  `            ``// count consecutive ` `            ``// 0's ` `            ``c1++;  ` `        ``} ` `        ``else` `        ``{ ` `            ``c1 = 0; ` ` `  `            ``// count consecutive ` `            ``// 1's ` `            ``c2++;  ` `        ``} ` `        ``if` `(c1 == m || c2 == m) ` `            ``return` `true``; ` `    ``} ` `    ``return` `false``; ` `} ` ` `  `// Driver Code ` `public` `static` `void` `Main ()  ` `{ ` `    ``String s = ``"001001"``; ` `    ``int` `m = 2; ` `     `  `    ``// function call ` `    ``if` `(check(s, m)) ` `        ``Console.WriteLine( ``"YES"``); ` `    ``else` `        ``Console.WriteLine( ``"NO"``); ` `} ` `} ` ` `  `// This code is contributed  ` `// by anuj_67. `

## PHP

 ` `

Output :

```YES
```

Time Complexity: O(N), where N is the length of the binary string.

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.

My Personal Notes arrow_drop_up Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.

Improved By : vt_m, Shivi_Aggarwal

Article Tags :
Practice Tags :

Be the First to upvote.

Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.