Minimum Deletions to Make String Balanced — Algorithm Visualization & Coding Challenge

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Understanding Minimum Deletions to Make String Balanced

Detailed explanation and reference materials

Problem Overview

Minimum Deletions to Make String Balanced

Medium

Topics

String
Dynamic Programming

Problem Statement

You are given a string s consisting only of characters 'a' and 'b'.

You can delete any number of characters in s to make s balanced.

A string is considered balanced if there is no pair of indices (i, j) such that:

i < j
s[i] = 'b'
s[j] = 'a'

In other words, all 'a's must come before any 'b's.

Return the minimum number of deletions needed to make s balanced.

Example 1

Input:

s = "aababbab"

Output:

Explanation:

You can either:

Delete characters at positions 2 and 6
"aababbab" → "aaabbb"
Delete characters at positions 3 and 6
"aababbab" → "aabbbb"

Example 2

Input:

s = "bbaaaaabb"

Output:

Explanation:

The only solution is to delete the first two characters.

Constraints

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

— Written by Saurabh Patil • B.Tech CSE • Software Developer

Reference Link

https://leetcode.com/problems/minimum-deletions-to-make-string-balanced/description/

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Java

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