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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? Minimum Window Substring - Given two strings s and t of lengths m and n respectively, return the minimum window substring of s such that every character in …

Can you solve this real interview question? Isomorphic Strings - Given two strings s and t, determine if they are isomorphic. Two strings s and t are isomorphic if the characters in s can be replaced to get …

Can you solve this real interview question? 3Sum - Given an integer array nums, return all the triplets [nums[i], nums[j], nums[k]] such that i != j, i != k, and j ...

Can you solve this real interview question? Concatenation of Array - Given an integer array nums of length n, you want to create an array ans of length 2n where ans[i] == nums[i] and ans[i + n] == …

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? Best Time to Buy and Sell Stock - You are given an array prices where prices[i] is the price of a given stock on the ith day. You want to maximize your profit by …