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DSA Problem Sheets

Data Structures & Algorithms

📋 70 Problems● Easy 33● Medium 32● Hard 5
Difficulty:AllEasy33Medium32Hard5
Topic:AllArrayPrefix SumHashingHash TableSliding WindowMathDynamic ProgrammingTwo PointerGreedyDequeSortingTwo Pointers
Showing 22 of 70 problems · String
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Title
Difficulty
22
Check If a Sentence Reads the Same Ignoring Case and Symbols
Easy
23
Valid Anagram
Easy
24
Valid Parentheses
Easy
31
Check If a String Contains a Permutation of Another
Medium
53
Reverse a String In-Place
Easy
54
Length of the Last Word in a Sentence
Easy
55
Longest Common Prefix of an Array of Strings
Easy
56
Reverse the Order of Words in a Sentence
Medium
57
Add Two Binary Strings
Easy
58
Compress a String Using Run-Length Encoding
Medium
59
Multiply Two Numbers Represented as Strings
Hard
60
Convert a Roman Numeral to an Integer
Medium
61
Remove the Outermost Parentheses From Every Primitive Group
Easy
62
Check If One String Is a Rotation of Another
Easy
63
Find the First Non-Repeating Character in a String
Easy
63
Find the First Non-Repeating Character in a String
Easy
64
Group Strings That Are Anagrams of Each Other
Medium
64
Group Strings That Are Anagrams of Each Other
Medium
65
Check if Two Strings Are Isomorphic
Easy
65
Check if Two Strings Are Isomorphic
Easy
66
Sort Characters of a String by Frequency
Medium
66
Sort Characters of a String by Frequency
Medium