# leetcode java solutions

A number is said to be happy number if replacing the number by the sum of the squares of its digits, and repeating the process makes the number equal to 1. if it does not become 1 and loops endlessly in a cycle which does not include 1, it is not a happy_number.. Note that this is a 2^n problem. Max Consecutive Ones Leetcode Solution - find the maximum number of consecutive 1s present in the_given array containing only 0s and 1s. Unsubscribe easily at any time. Lists. Use Git or checkout with SVN using the web URL. String handle: Split with space than reverse word, O(n) and O(n). Java Development. Return true because "leetcode" can be segmented as "leet code". Two points fast (next next) and slow (next) O(nlgn) and O(n), Recursion 1. No Spam. 4Solution Word Break. Requirements. Sort and find mean, O(mnlogmn) and O(1), Bottom-up or top-down recursion, O(n) and O(n), Quick union find with weights, O(nlogn) and O(n), Bottom-up or top-down DP, dp[n] = min(dp[n], dp[n - v_i]), where v_i is the coin, O(amount * n) and O(amount), 1. Java Development. Place odd and even number in odd and even place, not sort is needed. We can merge two sorted arrays to form an overall sorted array. LeetCode Java. Create a reverse word to index map, then for each word, check prefix and posfix, O(nk^2) and O(n), 1. For more problems watch out this space. Store index and check, O(logn) and O(logn), DFS (stack or recursion) get leaf value sequence and compare, O(n) and O(n), 1. Go through list and get length, then remove length-n, O(n) and O(n), Add a dummy head, then merge two sorted list in O(m+n), 1. Imaging letter a as 0, then the sum(t)-sum(s) is the result. TechLead Recommended for you. Hash implementation, mod is fine. House Robber II Leetcode Solution. Recursion with hash map, O(n) and O(n). Instructors. Instructors. Requirements. We can twice for left and right (reverse), O(n) and O(n), Update index1 and index2, and check distance, O(n) and O(1), Hash table and reverse string, O(n) and O(n), Hash and generate hash code for each string, O(n) and O(n), 1. Value (1, n) and index (0, n-1). Source code and videos categories please refer to: https://happygirlzt.com/codelist.html I did bottom up and recursion. Hash or table. O(n) and O(1), Queue, remove val in head when val < t - 3000, O(n) and O(n), Sort, then list duplicate and missing value in sorted list. Only push min, such that len(minStack)<=len(Stack) 2. Check from top left to bottom right, i,j == i + 1, j + 1. 1. Course content. Recursive check left, val and right, LCA is the split paths in tree, O(n) and O(n), The ans is [0,i -1] * [i+1, len- 1]. Contribute Question. Sort and insert (n - 1) / 2 from tail to correct position, O(nlogn) and O(1), 1. Linked lists are quite like arrays in their linear properties. Top-down O(n^2) and O(n), Bottom-up recursion with sentinel -1 O(n) and O(n), 1. coding interview. Thanks for different solutions. Add to Wishlist . Recursively generate result with previous result. We search each node and remember the maximum number of nodes used in some path. Status. Check it out, if you are interested in big data and deep learning. Reduce to two sum smaller, then binary search, O(n^2lgn) and O(1), Compute frequency, check number of odd occurrences <= 1 then palindrome, O(n) and O(n), 1. So, XOR then count 1. Contains Ads. Better solution is that reverse can be O(1) space in array. Coding Interview preparation. Reviews. I believe messy code is costing you. Tags . Last Edit: October 26, 2018 6:22 AM. LeetCode solutions written in Java using vscode leetcode plugin. Algorithms. Note that 12 * 60 is much less than 2^n or n^2. Find degree and value, then find smallest subarray (start and end with this value), O(n) and O(n), 1. Also, I build a website by GitHub Actions to host the code files by markdown files. Sort with condition, O(nlogn) and O(1), 1. Recursive. 253 LeetCode Java: Meeting Rooms – Medium Problem: Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],…] (si < ei), find the minimum number of conference rooms required. Contributing. Learn more. Sort and O(n^2) search with three points, The same as 3Sum, but we can merge pairs with the same sum, 1. Scan through blocks of tree, O(n) and O(n), 1. Unsubscribe easily at any time. Leetcode-Java-Solutions Solutions to Leetcode problems in Java Current Leetcode profile: Solved 800+ Problems Previous Leetcode profile: Solved 759 Problems. Recursion, note that when size of left (ld) or right (rd) is 0, then min = 1 + ld + rd, Recursion O(n) and O(n), max (left + node, right + node, left + node + right), Exclude non-alphanumeric characters and compare O(n), Set or hash, pop adjacency, O(n) and O(n), 1. Length of Palindrome is always 2n or 2n + 1. Python and Java full list. LeetCode Curated Algo 170 LeetCode Curated SQL 70 Top 100 Liked Questions Top Interview Questions ️ Top Amazon Questions Top Facebook Questions ⛽ Top Google Questions Ⓜ️ Top Microsoft Questions. Push min again when current top is min, such that len(minStack)=len(Stack), p.left = parent.right, parent.right = p.right, p.right = parent, parent = p.left, p = left, Store the pos and offset that is read by last read4, Maintain a sliding window that always satisfies such condition, 1. Java solution. Coding Interview preparation. If nothing happens, download Xcode and try again. English English [Auto] What you'll learn. Pick One . Each move is equal to minus one element in array, so the answer is the sum of all elements after minus min. Coding Style . The ultimate free app that helps you to prepare for algorithm job interview questions. Go through bits, 1 skip next, O(n) and O(1), Seach the array to find a place where left sum is equal to right sum, O(n) and O(1), Brute Force check every digit, O(nlogD) and O(1), 1. coding interview. 278. lzb700m 1061. Sort index by value, then transfer problem into finding max gap between index, O(nlogn) and O(1), 1. If nothing happens, download GitHub Desktop and try again. Recursively DFS with root.left.left and root.left.right check. We can use recursion to traverse the binary tree. Merge two sorted lists and compute median, O(m + n) and O(m + n). Get A Weekly Email With Trending Projects For These Topics. If nothing happens, download GitHub Desktop and try again. Table of contents 1021. Coding Interview preparation. Leetcode Questions Solutions Explained 6 Solving Microsoft, Google, Airbnb, Uber, Amazon interview questions New Rating: 5.0 out of 5 5.0 (1 rating) 478 students Created by Kado Data. Remove Outermost Parentheses \$\star\$ 1022. DFS with stack or recursive, O(n) and O(n), Let V == N, then: 1. Timothy H Chang 53 views. Category - All. Leetcode Questions Solutions Explained 8 Solving Microsoft, Google, Airbnb, Uber, Amazon interview questions New Rating: 0.0 out of 5 0.0 (0 ratings) 530 students Created by Kado Data. Remember solutions are only solutions to given problems. Recursively travese the whole tree, O(n^2), Build a char count list with 26-256 length. Solution 1: Using Recursion. which has an average pay of \$10,000+. 1.5K VIEWS. 5. Solved. Use Git or checkout with SVN using the web URL. Sort based on frequency and alphabetical order, O(nlgn) and O(n), 1. Recursively check s[left == end, when not equal delete left or right. Backtracking to ensure that next step is False, O(n!!) Set is recommended. Work fast with our official CLI. This path may or may not pass through the root. Course content. Leetcode - Reverse Bits (Python) - Duration: 4:52. 1. If you see an problem that you’d like to see fixed, the best way to make it happen is to help out by submitting a pull request implementing it. LeetCode Solutions Getting Started. A great tool that can help you land a software engineer job in big tech companies like Google, Facebook, Amazon, MicroSoft, Uber, etc. Maintain a sliding window with at most k distinct characters and a count for this window. Handle each 2k until reaching end, On(n) and O(n). Welcome to "LeetCode in Java: Algorithms Coding Interview Questions" course! O(n). O(nlgn) and O(n), Add a stack named inStack to help going through pushed and popped. Find missing by n * (n - 1)/2 - sum(nums), 1. Get the len and check left and right with 10^len, 10, Add all curr, if curr > prev, then need to subtract 2 * prev, 1. 0/1713 Solved - Easy 0 Medium 0 Hard 0. Categories LeetCode Solutions Tags Amazon, Apple, Binary Search, Bloomberg, Easy, Google, lyft, Math, Microsoft, Uber Post navigation. Binary search hourse in heater array, O(nlogn) and O(1), 1. In this course, you'll have a detailed, step by step explanation of classical hand-picked LeetCode Problems where you'll learn about the optimum ways to solve technical coding interview question.This is the course I wish I had when I was preparing myself for the interviews. Using the web URL for Leetcode ( inspired by haoel 's Leetcode ) to host code! Complexity Analysis of sum of left Leaves Leetcode Solutions leet code '' /2 - sum ( nums ), V! 759 problems Method ; Complexity Analysis of sum of node.val and right.val Complexity Analysis of sum left! Length of Palindrome is always 2n or 2n + 1 C++, Java, and Python as much I. Desktop and try again j + 1, j == I + 1 to it... ) - Duration: 4:52 Hard 0 minStack ) < =len ( stack ) 2 with condition, O n... 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