Strings

25 problems — 11 easy, 12 medium, 2 hard.

#	Title	Difficulty	Frequency
3	Longest Substring Without Repeating Characters	medium	frequently asked
5	Longest Palindromic Substring	medium	frequently asked
6	Zigzag Conversion	medium	common
14	Longest Common Prefix	easy	foundational
20	Valid Parentheses	easy	foundational
28	Find the Index of the First Occurrence in a String	easy	foundational
49	Group Anagrams	medium	frequently asked
58	Length of Last Word	easy	foundational
76	Minimum Window Substring	hard	common
125	Valid Palindrome	easy	foundational
151	Reverse Words in a String	medium	common
214	Shortest Palindrome	hard	advanced
242	Valid Anagram	easy	foundational
271	Encode and Decode Strings	medium	frequently asked
344	Reverse String	easy	foundational
387	First Unique Character in a String	easy	foundational
424	Longest Repeating Character Replacement	medium	common
443	String Compression	medium	common
520	Detect Capital	easy	foundational
763	Partition Labels	medium	common
771	Jewels and Stones	easy	foundational
791	Custom Sort String	medium	common
880	Decoded String at Index	medium	common
937	Reorder Data in Log Files	medium	common
1108	Defanging an IP Address	easy	warm up