# Count of substrings of a Binary string containing only 1s

Given a binary string of length **N**, we need to find out how many substrings of this string contain only 1s.

**Examples:**

Input:S = “0110111”Output:9Explanation:

There are 9 substring with only 1’s characters.

“1” comes 5 times.

“11” comes 3 times.

“111” comes 1 time.

Input:S = “000”Output:0

**Approach**: The idea is to traverse the binary string and count the consecutive ones in the string. Below is the illustration of the approach:

- Traverse the given binary string from index 0 to length – 1
- Count the number of consecutive “1” till index i.
- For each new character str[i], there will be more substring with all character’s as “1”

Below is the implementation of the above approach:

## C++

`// C++ implementation to find` `// count of substring containing` `// only ones` `#include <bits/stdc++.h>` `using` `namespace` `std;` `// Function to find the total number` `// of substring having only ones` `int` `countOfSubstringWithOnlyOnes(string s)` `{` ` ` `int` `res = 0, count = 0;` ` ` `for` `(` `int` `i = 0; i < s.length(); i++) {` ` ` `count = s[i] == ` `'1'` `? count + 1 : 0;` ` ` `res = (res + count);` ` ` `}` ` ` `return` `res;` `}` `// Driver Code` `int` `main()` `{` ` ` `string s = ` `"0110111"` `;` ` ` `cout << countOfSubstringWithOnlyOnes(s)` ` ` `<< endl;` ` ` `return` `0;` `}` |

## Java

`// Java implementation to find` `// count of substring containing` `// only ones` `class` `GFG{` ` ` `// Function to find the total number` `// of substring having only ones` `static` `int` `countOfSubstringWithOnlyOnes(String s)` `{` ` ` `int` `res = ` `0` `, count = ` `0` `;` ` ` `for` `(` `int` `i = ` `0` `; i < s.length(); i++)` ` ` `{` ` ` `count = s.charAt(i) == ` `'1'` `? count + ` `1` `: ` `0` `;` ` ` `res = (res + count);` ` ` `}` ` ` `return` `res;` `}` `// Driver code` `public` `static` `void` `main(String[] args)` `{` ` ` `String s = ` `"0110111"` `;` ` ` ` ` `System.out.println(countOfSubstringWithOnlyOnes(s));` `}` `}` `// This code is contributed by dewantipandeydp` |

## Python3

`# Python3 implementation to find` `# count of substring containing` `# only ones` `# Function to find the total number` `# of substring having only ones` `def` `countOfSubstringWithOnlyOnes(s):` ` ` `count ` `=` `0` ` ` `res ` `=` `0` ` ` ` ` `for` `i ` `in` `range` `(` `0` `,` `len` `(s)):` ` ` `if` `s[i] ` `=` `=` `'1'` `:` ` ` `count ` `=` `count ` `+` `1` ` ` `else` `:` ` ` `count ` `=` `0` `;` ` ` ` ` `res ` `=` `res ` `+` `count` ` ` ` ` `return` `res` `# Driver Code` `s ` `=` `"0110111"` `print` `(countOfSubstringWithOnlyOnes(s))` `# This code is contributed by jojo9911` |

## C#

`// C# implementation to find count` `// of substring containing only ones` `using` `System;` `class` `GFG{` ` ` `// Function to find the total number` `// of substring having only ones` `static` `int` `countOfSubstringWithOnlyOnes(` `string` `s)` `{` ` ` `int` `res = 0, count = 0;` ` ` ` ` `for` `(` `int` `i = 0; i < s.Length; i++)` ` ` `{` ` ` `count = s[i] == ` `'1'` `? count + 1 : 0;` ` ` `res = (res + count);` ` ` `}` ` ` `return` `res;` `}` `// Driver code` `public` `static` `void` `Main(` `string` `[] args)` `{` ` ` `string` `s = ` `"0110111"` `;` ` ` ` ` `Console.Write(countOfSubstringWithOnlyOnes(s));` `}` `}` `// This code is contributed by rutvik_56` |

## Javascript

`<script>` `// Javascript implementation to find` `// count of substring containing` `// only ones` `// Function to find the total number` `// of substring having only ones` `function` `countOfSubstringWithOnlyOnes(s)` `{` ` ` `var` `res = 0, count = 0;` ` ` `for` `(` `var` `i = 0; i < s.length; i++) {` ` ` `count = s[i] == ` `'1'` `? count + 1 : 0;` ` ` `res = (res + count);` ` ` `}` ` ` `return` `res;` `}` `// Driver Code` `var` `s = ` `"0110111"` `;` `document.write( countOfSubstringWithOnlyOnes(s));` `</script>` |

**Output**

9

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