Design and implement a data structure for a Least Frequently Used (LFU) cache. Implement the LFUCache class: Example 1: Input [“LFUCache”, “put”, “put”, “get”, “put”, “get”, “get”, “put”, “get”, “get”, “get”] [[2], [1, 1], [2, 2], [1], [3, 3], [2], [3], [4, 4], [1], [3], [4]] Output [null, null, null, 1, null, -1, 3, null, -1, 3, 4] This… Continue reading
Category: Algorithm
Maximum of all Subarrays of size K | LeetCode #239
You are given an array of integers nums, there is a sliding window of size k which is moving from the very left of the array to the very right. You can only see the k numbers in the window. Each time the sliding window moves right by one position. Return the max sliding window of size K Example 1: Input:… Continue reading
Binary Tree Level Order Traversal
Given the root of a binary tree, return the level order traversal of its nodes’ values. (i.e., from left to right, level by level). Example: Input: root = [3,9,20,null,null,15,7] Output: [[3],[9,20],[15,7]] Input: root = [1] Output: [[1]] Algorithm: Since we have to traverse the tree level wise and need to process node from left to right, we can… Continue reading
Program to move all zeroes to the end
Given an integer array nums, move all 0’s to the end of it while maintaining the relative order of the non-zero elements. Note that you must do this in-place without making a copy of the array. Example 1: Input: nums = [0,1,0,3,12]Output: [1,3,12,0,0]Example 2: Input: nums = [0]Output: [0]
Program to reverse word in a string
Given a string s, reverse the order of characters in each word within a sentence while still preserving whitespace and initial word order. Example 1: Input: s = “Let’s take LeetCode contest”Output: “s’teL ekat edoCteeL tsetnoc”Example 2: Input: s = “God Ding”Output: “doG gniD” Solution: string reverseWords(string s) {int n = s.length();if(n==0){return s;} };