Package g1501_1600.s1513_number_of_substrings_with_only_1s

Class Solution

java.lang.Object
g1501_1600.s1513_number_of_substrings_with_only_1s.Solution
public class Solution extends java.lang.Object
1513 - Number of Substrings With Only 1s.

Medium

Given a binary string s, return the number of substrings with all characters 1’s. Since the answer may be too large, return it modulo 109 + 7.

Example 1:

Input: s = “0110111”

Output: 9

Explanation: There are 9 substring in total with only 1’s characters. “1” -> 5 times. “11” -> 3 times. “111” -> 1 time.

Example 2:

Input: s = “101”

Output: 2

Explanation: Substring “1” is shown 2 times in s.

Example 3:

Input: s = “111111”

Output: 21

Explanation: Each substring contains only 1’s characters.

Constraints:

  • 1 <= s.length <= 105
  • s[i] is either '0' or '1'.

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    numSub(java.lang.String s)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • numSub

      public int numSub(java.lang.String s)