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Md Ariful Haque @mah-shamim

Minimum Swaps For Balanced String

Minimum swaps to balance string: track imbalance & max_imbalance, swap (max_imbalance + 1) / 2 times. Time complexity O(n), space complexity O(1).

1963. Minimum Number of Swaps to Make the String Balanced
Difficulty: Medium
Topics: Two Pointers, String, Stack, Greedy
You are given a 0-indexed string s of even length n. The string consists of exactly n / 2 opening brackets '[' and n / 2 closing brackets ']'.
A string is called balanced if and only if:

It is the empty string, or
It can be written as AB, where both A and B are balanced strings, or
It can be written as [C], where C is a balanced string.

You may swap the brackets at any two indices any number of times.
Return the minimum number of swaps to make s balanced.
Example 1:

Input...