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1768. Merge Strings Alternately You are given two strings word1 and word2. Merge the strings by adding letters in alternating order, starting with word1. If a string is longer than the other, append the additional letters onto the end of the merged string.Return the merged string. Example 1:Input: word1 = "abc", word2 = "pqr"Output: "apbqcr"Explanation: The merged string will be merged as so:wor..

901. Online Stock Span Design an algorithm that collects daily price quotes for some stock and returns the span of that stock's price for the current day.The span of the stock's price in one day is the maximum number of consecutive days (starting from that day and going backward) for which the stock price was less than or equal to the price of that day.For example, if the prices of the stock in ..

739. Daily Temperatures Given an array of integers temperatures represents the daily temperatures, return an array answer such that answer[i] is the number of days you have to wait after the ith day to get a warmer temperature. If there is no future day for which this is possible, keep answer[i] == 0 instead. Example 1:Input: temperatures = [73,74,75,71,69,72,76,73]Output: [1,1,4,2,1,1,0,0]Examp..

452. Minimum Number of Arrows to Burst Balloons There are some spherical balloons taped onto a flat wall that represents the XY-plane. The balloons are represented as a 2D integer array points where points[i] = [xstart, xend] denotes a balloon whose horizontal diameter stretches between xstart and xend. You do not know the exact y-coordinates of the balloons.Arrows can be shot up directly vertic..

435. Non-overlapping Intervals Given an array of intervals intervals where intervals[i] = [starti, endi], return the minimum number of intervals you need to remove to make the rest of the intervals non-overlapping.Note that intervals which only touch at a point are non-overlapping. For example, [1, 2] and [2, 3] are non-overlapping. Example 1:Input: intervals = [[1,2],[2,3],[3,4],[1,3]]Output: 1..

Leetcode 75 질문 유형 및 유투브 솔루션 링크 정리 https://docs.google.com/spreadsheets/d/1BiY_cRfXI9yJPaU75RFcfVRN2OF1CilpiwX5cdHXRoU/edit?usp=sharing  김현구: Leetcode 75 Questions (NeetCode on yt)trick: I though use trie to store the grid, reverse thinking, instead store dictionary words, dfs on each cell, check if cell's char exists as child of root node in trie, if it does, update currNode, and check neighbors..

1268. Search Suggestions System You are given an array of strings products and a string searchWord.Design a system that suggests at most three product names from products after each character of searchWord is typed. Suggested products should have common prefix with searchWord. If there are more than three products with a common prefix return the three lexicographically minimums products.Return a..

208. Implement Trie (Prefix Tree) https://youtu.be/oobqoCJlHA0?si=rB7vqpOg4d0DiFd1 https://youtu.be/j7Zkw5XWe_Q?si=-yC7nuoxBULmLBuD 이 문제는 Trie(트라이) 자료 구조를 구현하는 것입니다. Trie는 문자열을 효율적으로 저장하고 검색하기 위해 사용되는 트리 형태의 자료 구조입니다. 이 자료 구조는 주로 자동완성, 단어 검색, 접두사 검색과 같은 작업에서 사용됩니다.  Code  # TrieNode 클래스: Trie의 각 노드를 정의class TrieNode: def __init__(self): self.children = {} # 자식 노드를 저장할 해시맵. 키는 문자, 값은 T..

1318. Minimum Flips to Make a OR b Equal to c  Given 3 positives numbers a, b and c. Return the minimum flips required in some bits of a and b to make ( a OR b == c ). (bitwise OR operation).Flip operation consists of change any single bit 1 to 0 or change the bit 0 to 1 in their binary representation. Example 1:Input: a = 2, b = 6, c = 5Output: 3Explanation: After flips a = 1 , b = 4 , c = 5 su..

338. Counting Bits Given an integer n, return an array ans of length n + 1 such that for each i (0  ans[i] is the number of 1's in the binary representation of i. Example 1:Input: n = 2Output: [0,1,1]Explanation:0 --> 01 --> 12 --> 10Example 2:Input: n = 5Output: [0,1,1,2,1,2]Explanation:0 --> 01 --> 12 --> 103 --> 114 --> 1005 --> 101 Constraints:0  Follow up:It is very easy to come up with a s..