Binary String
Submissions: 14845   Accuracy:

49.94%

  Difficulty: Basic   Marks: 1
Associated Course(s):   Sudo Placement 2019

Given a binary string S. The task is to count the number of substrings that start and end with 1. For example, if the input string is “00100101”, then there are three substrings “1001”, “100101” and “101”.

Input:
The first line of input contains an integer T denoting the number of test cases. Each test case consist of an integer 'N' denoting the string length and next line is followed by a binary string.

Output:
For each testcase, in a new line, print the number of substring starting and ending with 1 in a separate line.

Constraints:
1 ≤ T ≤ 100
1 ≤ |S| ≤ 104

Example:
Input:
2
4
1111
5
01101

Output:
6
3

Example:
Testcase 1:
There are 6 substrings from the given string. They are 11, 11, 11, 111, 111, 1111.
Testcase 2: There 3 substrings from the given string. They are 11, 101, 1101.

 

** For More Input/Output Examples Use 'Expected Output' option **

Author: shef5


If you have purchased any course from GeeksforGeeks then please ask your doubt on course discussion forum. You will get quick replies from GFG Moderators there.



Need help with your code? Please use ide.geeksforgeeks.org, generate link and share the link here.

to report an issue on this page.