Level up your coding skills and quickly land a job. This is the best place to expand your knowledge and get prepared for your next interview.

Level up your coding skills and quickly land a job. This is the best place to expand your knowledge and get prepared for your next interview.

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Can you solve this real interview question? Car Pooling - There is a car with capacity empty seats. The vehicle only drives east (i.e., it cannot turn around and drive west). You are given the integer …

Can you solve this real interview question? Surrounded Regions - You are given an m x n matrix board containing letters 'X' and 'O', capture regions that are surrounded: * Connect: A cell is connected to …

Can you solve this real interview question? Range Sum Query - Immutable - Given an integer array nums, handle multiple queries of the following type: 1. Calculate the sum of the elements of nums …

Can you solve this real interview question? Valid Palindrome - A phrase is a palindrome if, after converting all uppercase letters into lowercase letters and removing all non-alphanumeric characters, …

Can you solve this real interview question? 4Sum - Given an array nums of n integers, return an array of all the unique quadruplets [nums[a], nums[b], nums[c], nums[d ...

Can you solve this real interview question? Find the Town Judge - In a town, there are n people labeled from 1 to n. There is a rumor that one of these people is secretly the town judge. If the town judge …

Use two pointers to create the new array of 2n elements. The first starting at the beginning and the other starting at (n+1)th position. Alternate between them and create the new array.