Number of Matching Subsequences

Keyboard Row

Decode String

Minimum Add to Make Parentheses Valid

Implement strStr()

Longest Common Prefix

Length of Last Word

Power of 2

Valid Palindrome

Valid Palindrome II

Verifying an Alien Dictionary

Add Binary

Last Substring in Lexicographical Order

Roman to Integer

Integer to Roman

String to Integer (atoi)

Multiply Strings

Reverse Words in a String

Minimum Characters required to make a String Palindromic