Below is a high-yield, pattern-driven set of string problems. This set is designed to cover all essential concepts:

• two pointers
• sliding window
• hashing / frequency maps
• parsing
• palindrome patterns
• substring / subsequence logic

1. Basic String Traversal

Core Skill

• Iterate and manipulate characters

Problems

• Reverse String
• Reverse Words in a String

Concepts

• in-place swaps
• splitting and joining

2. Two Pointers (Palindrome Pattern)

Core Skill