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[Leetcode/파이썬] 452. Minimum Number of Arrows to Burst Balloons

Minimum Number of Arrows to Burst BalloonsThere 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 vertically (..

[Leetcode/파이썬] 208. Implement Trie (Prefix Tree)

Implement Trie (Prefix Tree)A trie (pronounced as "try") or prefix tree is a tree data structure used to efficiently store and retrieve keys in a dataset of strings. There are various applications of this data structure, such as autocomplete and spellchecker.Implement the Trie class:Trie() Initializes the trie object.void insert(String word) Inserts the string word into the trie.boolean search(S..

[Leetcode/파이썬] 101. Symmetric Tree

Symmetric TreeGiven the root of a binary tree, check whether it is a mirror of itself (i.e., symmetric around its center). Example 1:Input: root = [1,2,2,3,4,4,3]Output: trueExample 2:Input: root = [1,2,2,null,3,null,3]Output: false Constraints:The number of nodes in the tree is in the range [1, 1000].-100 Follow up: Could you solve it both recursively and iteratively? # Definition for a binary..