레벨업 일지

문제 https://leetcode.com/problems/validate-stack-sequences/description/ Validate Stack Sequences - LeetCode Can you solve this real interview question? Validate Stack Sequences - Given two integer arrays pushed and popped each with distinct values, return true if this could have been the result of a sequence of push and pop operations on an initially empty stack leetcode.com 스택의 push , pop 연산이 주어..

문제 https://leetcode.com/problems/removing-stars-from-a-string/description/ Removing Stars From a String - LeetCode Can you solve this real interview question? Removing Stars From a String - You are given a string s, which contains stars *. In one operation, you can: * Choose a star in s. * Remove the closest non-star character to its left, as well as remove the star it leetcode.com 알아야 할 개념 Stri..

문제 https://leetcode.com/problems/edit-distance/submissions/931398157/ 알아야 할 개념 다이나믹 프로그래밍 풀이 문제에서 문자를 삭제, 추가, 교체 하는 작업을 하나의 단위로 주어졌다. 풀이는 다음과 같다. 주어진 문자열 2개를 문자 배열로 만든다. 선형 탐색으로 0행과 0열을 초기화 한다. 2중 for문을 돌면서 다음을 수행한다. 문자열 1 의 i 번째 문자와, 문자열 2 의 j번째 문자가 같으면 [i-1][j-1] 의 값을 가져온다. 다르면, 현재 위치 (i 행 j 열) 에서 [i-1][j] , [i-1][j-1] , [i][j-1] 3개의 값의 최솟값에 1 을 더한 값을 할당한다. 정답을 리턴한다. 문자열 연산 수의 최솟값 구하기 는 잘 알려진 ..

문제 3Sum - LeetCode 3Sum - LeetCode 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 != k, and nums[i] + nums[j] + nums[k] == 0. Notice that the solution set must not contain du leetcode.com 알아야 할 개념 투포인터 풀이 3가지의 합이 0 이되는 것을 찾는 문제. 접근법은 투포인터를 사용하여 문제 풀이 하였다. 풀이 알고리즘은 다음과 같다. 주어진 배열을 ..

문제 https://leetcode.com/problems/count-unreachable-pairs-of-nodes-in-an-undirected-graph/description/ Count Unreachable Pairs of Nodes in an Undirected Graph - LeetCode Can you solve this real interview question? Count Unreachable Pairs of Nodes in an Undirected Graph - You are given an integer n. There is an undirected graph with n nodes, numbered from 0 to n - 1. You are given a 2D integer arr..

문제 https://leetcode.com/problems/reorder-routes-to-make-all-paths-lead-to-the-city-zero/ Reorder Routes to Make All Paths Lead to the City Zero - LeetCode Can you solve this real interview question? Reorder Routes to Make All Paths Lead to the City Zero - There are n cities numbered from 0 to n - 1 and n - 1 roads such that there is only one way to travel between two different cities (this netwo..

문제 https://leetcode.com/problems/number-of-operations-to-make-network-connected/description/ Number of Operations to Make Network Connected - LeetCode Can you solve this real interview question? Number of Operations to Make Network Connected - There are n computers numbered from 0 to n - 1 connected by ethernet cables connections forming a network where connections[i] = [ai, bi] represents a con..

문제 https://leetcode.com/problems/minimum-score-of-a-path-between-two-cities/description/ Minimum Score of a Path Between Two Cities - LeetCode Can you solve this real interview question? Minimum Score of a Path Between Two Cities - You are given a positive integer n representing n cities numbered from 1 to n. You are also given a 2D array roads where roads[i] = [ai, bi, distancei] indicates that..