2464. Time Needed to Rearrange a Binary String

Medium
String
Dynamic Programming
Simulation

Description

You are given a binary string s. In one second, all occurrences of "01" are simultaneously replaced with "10". This process repeats until no occurrences of "01" exist.

Return the number of seconds needed to complete this process.

 

Example 1:

Input: s = "0110101"
Output: 4
Explanation: 
After one second, s becomes "1011010".
After another second, s becomes "1101100".
After the third second, s becomes "1110100".
After the fourth second, s becomes "1111000".
No occurrence of "01" exists any longer, and the process needed 4 seconds to complete,
so we return 4.

Example 2:

Input: s = "11100"
Output: 0
Explanation:
No occurrence of "01" exists in s, and the processes needed 0 seconds to complete,
so we return 0.

 

Constraints:

  • 1 <= s.length <= 1000
  • s[i] is either '0' or '1'.

 

Follow up:

Can you solve this problem in O(n) time complexity?

Hints

Hint 1
Try replicating the steps from the problem statement.
Hint 2
Perform the replacements simultaneously, and return the number of times the process repeats.

Statistics

Acceptance
52.7%
Submissions
81,605
Accepted
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