Solution: Number of Substrings Containing All Three Characters

Explore how to use the sliding window technique to count substrings containing at least one 'a', 'b', and 'c' in a string. Understand how to expand and shrink the window to efficiently identify valid substrings, while tracking character frequencies and optimizing with O(n) time complexity. This lesson helps you implement a scalable solution to solve substring problems involving multiple character constraints.