Qualcomm

6 problems asked at Qualcomm.

Easy (4)

Implement Queue using Stacks (LeetCode 232)

Stack, Queue

Stack using Queue (LeetCode 225)

Stack, Queue

Two Sum (Leetcode 1)

Two Pointers, Arrays

Valid Parentheses (Leetcode 20)

Stack, Strings

Hard (2)

Next Permutation (Leetcode 31)

Arrays, Greedy, Two Pointers

Trapping Rain Water (LC 42)

Two Pointers, Prefix and Suffix Arrays, Stack