DSA Exam UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
What data structure is best for counting characters? - CORRECT ANSWER Hash map /
dictionary
How to check if two strings are anagrams? - CORRECT ANSWER Counter(s) == Counter(t) -
compare frequency maps
Group Anagrams key idea? - CORRECT ANSWER sorted string as hashmap key
Time complexity of Valid Anagram? - CORRECT ANSWER O(n)
Common pattern for string interview problems? - CORRECT ANSWER Hash map frequency
counting
When solving Group Anagrams, the key idea becomes - CORRECT ANSWER signature =
frequency array of 26 letters
QUESTIONS AND CORRECT ANSWERS
What data structure is best for counting characters? - CORRECT ANSWER Hash map /
dictionary
How to check if two strings are anagrams? - CORRECT ANSWER Counter(s) == Counter(t) -
compare frequency maps
Group Anagrams key idea? - CORRECT ANSWER sorted string as hashmap key
Time complexity of Valid Anagram? - CORRECT ANSWER O(n)
Common pattern for string interview problems? - CORRECT ANSWER Hash map frequency
counting
When solving Group Anagrams, the key idea becomes - CORRECT ANSWER signature =
frequency array of 26 letters
