Problem Given an integer array nums that does not contain any zeros, find the largest positive integer k such that -k also exists in the array. Return the positive integer k. If there is no such integer, return -1. Examples Example 1: Input: nums = [-1,2,-3,3] Output: 3 Explanation: 3 is the only valid k we can find in the array. ...
2Sum Problem Problem Given a 0-indexed string word and a character ch, reverse the segment of word that starts at index 0 and ends at the index of the first occurrence of ch (inclusive). If the character ch does not exist in word, do nothing. For example, if word = "abcdefd" and ch = "d", then you should reverse the segment that starts at 0 and ends at 3 (inclusive). The resulting string will be "dcbaefd". Return the resulting string. ...
Find First Unique Character From a Stream of Characters Problem Given a string A denoting a stream of lowercase alphabets. You have to make new string B. B is formed such that we have to find first non-repeating character each time a character is inserted to the stream and append it at the end to B. If no non-repeating character is found then append ’#’ at the end of B. ...
Problem Write a method to shuffle a deck of cards. It must be a perfect shuffle – in other words, each 52! permutations of the deck has to be equally likely. Assume that you are given a random number generator which is perfect. OR How can you shuffle an array in O(n) time and O(1) space? For example, if input is an array of (1, 2, 3, 4, 5), one of the output can be (5, 4, 3, 2, 1) or (4, 2, 3, 1, 5). ...
Problem You are given an n x n 2D matrix representing an image, rotate the image by 90 degrees (clockwise). Another way to ask the same problem Given an image represented by an NxN matrix, where each pixel in the image is 4 bytes, write a method to rotate the image by 90 degrees. Can you do this in place? Examples Example 1: ...
Problem Given two integer arrays nums1 and nums2, return an array of their intersection. Each element in the result must appear as many times as it shows in both arrays and you may return the result in any order. Examples Example 1: Input: nums1 = [1,2,2,1], nums2 = [2,2] Output: [2,2] ...
Problem Given two integer arrays nums1 and nums2, return an array of their intersection. Each element in the result must be unique and you may return the result in any order. Examples Example 1: Input: nums1 = [1, 2, 2, 1], nums2 = [2, 2] Output: [2] ...
Problem Given an integer array nums where every element appears three times except for one, which appears exactly once. Find the single element and return it. You must implement a solution with a linear runtime complexity and use only constant extra space. Examples Example 1: Input : nums = [1, 2, 4, 3, 3, 2, 2, 3, 1, 1] Output : 4 ...
Problem Given an integer array nums and an integer k, return the kth largest element in the array. Note that it is the kth largest element in the sorted order, not the kth distinct element. Example 1: Input: nums = [3,2,1,5,6,4], k = 2 Output: 5 Example 2: Input: nums = [3,2,3,1,2,4,5,5,6], k = 4 Output: 4 ...
Problem Input - array A with n distinct numbers and a number i ∈ {1, 2, …, n} Output : ith order statistic i.e. ith smallest element of the input array Solution We have already seen multiple solutions here - Kth OR Nth Smallest Element in an Array. Here will focus on Linear time or O(n) solution. Finding the ith smallest element may seem difficult at first, but is it possible to find some O(n) or linear time solution. ...