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Number of Substrings With Only 1s

Medium

You receive a binary string s, provide the count of substrings with all characters 1 's. Since the answer may be too large, provide it modulo 10^9+ 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 includes only 1's characters.

Constraints

  • 1 <= s.length <= 10^5
  • s[i] is either '0' or '1'.

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