TikTok

11 problems asked at TikTok.

Easy (3)

Implement Queue using Stacks (LeetCode 232)

Stack, Queue

Two Sum (Leetcode 1)

Two Pointers, Arrays

Valid Parentheses (Leetcode 20)

Stack, Strings

Medium (3)

Gas Station (Leetcode 134)

Arrays, Greedy, Prefix Sum

Group Anagrams (Leetcode 49)

Arrays, Strings, Sorting...

Remove Duplicate Letters / Smallest Subsequence of Distinct Characters (Leetcode 316 / 1081)

Strings, Greedy, Hashing...

Hard (4)

Largest Rectangle in Histogram (leetcode 84)

Arrays, Stack

N-Queens (Leetcode 51 & 52)

Backtracking, Maths, Recursion...

Next Permutation (Leetcode 31)

Arrays, Greedy, Two Pointers

Trapping Rain Water (LC 42)

Two Pointers, Prefix and Suffix Arrays, Stack

Not Specified (1)

Best Time to Buy and Sell Stock

Arrays, DP