LeetCode in Swift: Word Search

Problem Statement Given a 2D board and a word, find if the word exists in the grid. The word can be constructed from letters of sequentially adjacent cell, where “adjacent” cells are those horizontally or vertically neighboring. The same letter cell may not be used more than once. For example, Given board =

word Continue reading...

LeetCode in Swift: Reverse Words in a String

Problem Statement Given an input string, reverse the string word by word. For example: Given s = “the sky is blue“, return “blue is sky the“. Clarification: What constitutes a word? A sequence of non-space characters constitutes a word. Could the input string contain leading or trailing spaces? Yes. However, your reversed string should not Continue reading...

LeetCode in Swift: Binary Tree Level Order Traversal II

Problem Statement Given a binary tree, return the bottom-up level order traversal of its nodes’ values. (ie, from left to right, level by level from leaf to root). For example: Given binary tree {3,9,20,#,#,15,7},

return its bottom-up level order traversal as:

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LeetCode in Swift: Binary Tree Level Order Traversal

Problem Statement Given a binary tree, return the level order traversal of its nodes’ values. (ie, from left to right, level by level). For example: Given binary tree {3,9,20,#,#,15,7},

return its level order traversal as:

Original LeetCode problem page My Solution in Swift Continue reading...