Code & Beyond

문제Given a string s, remove duplicate letters so that every letter appears once and only once. You must make sure your result is the smallest in lexicographical order among all possible results. 주어진 string s에서 중복된 문자를 제거사전 정렬에서 가장 작은 결과를 리턴 (abc 예시입력1Input: s = "bcabc" 출력1Output: "abc" 'b' 와 'c'는 중복된 문자이므로 하나씩만 남기고 제거되지만, 'a'가 가장 앞에 올 경우 사전 순으로 더 작은 문자열이 되기 때문에 'bca'가 아닌 'abc'가 정답이 된다. 입력2Inpu..

문제Given a binary tree, find its minimum depth.The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. Note: A leaf is a node with no children. 입력root = [3,9,20,null,null,15,7] 출력2 제한The number of nodes in the tree is in the range [0, 105].-1000 풀이1 (js)/** * Definition for a binary tree node. * function TreeNode(val, left, right) { * ..

문제Given the root of a binary tree, return the inorder traversal of its nodes' values. 입력root = [1,null,2,3] 출력[1,3,2] 제한The number of nodes in the tree is in the range [0, 100].-100 풀이1 (js)/** * Definition for a binary tree node. * class TreeNode { * val: number * left: TreeNode | null * right: TreeNode | null * constructor(val?: number, left?: TreeNode | null, right?: TreeNod..