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문제 https://leetcode.com/problems/minimum-number-of-vertices-to-reach-all-nodes/description/ Minimum Number of Vertices to Reach All Nodes - LeetCode Can you solve this real interview question? Minimum Number of Vertices to Reach All Nodes - Given a directed acyclic graph, with n vertices numbered from 0 to n-1, and an array edges where edges[i] = [fromi, toi] represents a directed edge from leet..

문제 https://leetcode.com/problems/swapping-nodes-in-a-linked-list/description/ Swapping Nodes in a Linked List - LeetCode Can you solve this real interview question? Swapping Nodes in a Linked List - You are given the head of a linked list, and an integer k. Return the head of the linked list after swapping the values of the kth node from the beginning and the kth node from t leetcode.com 알아야 할 개..

문제 https://leetcode.com/problems/substring-with-concatenation-of-all-words/description/ Substring with Concatenation of All Words - LeetCode Can you solve this real interview question? Substring with Concatenation of All Words - You are given a string s and an array of strings words. All the strings of words are of the same length. A concatenated substring in s is a substring that contains all l..

문제 https://leetcode.com/problems/range-sum-query-mutable/ Range Sum Query - Mutable - LeetCode Can you solve this real interview question? Range Sum Query - Mutable - Given an integer array nums, handle multiple queries of the following types: 1. Update the value of an element in nums. 2. Calculate the sum of the elements of nums between indices lef leetcode.com 알아야 할 개념 세그먼트 트리 풀이 풀이 알고리즘은 다음과 ..

문제 https://leetcode.com/problems/maximum-width-of-binary-tree/description/ Maximum Width of Binary Tree - LeetCode Can you solve this real interview question? Maximum Width of Binary Tree - Given the root of a binary tree, return the maximum width of the given tree. The maximum width of a tree is the maximum width among all levels. The width of one level is defined as leetcode.com 알아야 할 개념 BFS 탐..

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/most-frequent-subtree-sum/description/ Most Frequent Subtree Sum - LeetCode Can you solve this real interview question? Most Frequent Subtree Sum - Given the root of a binary tree, return the most frequent subtree sum. If there is a tie, return all the values with the highest frequency in any order. The subtree sum of a node is de leetcode.com 가장 많은 Subtree Sum 빈..

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..