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* refactor: encode & decode Tree * style: build warning * feat: add Swift codes for array_representation_of_tree article
42 lines
1.1 KiB
Swift
42 lines
1.1 KiB
Swift
/**
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* File: binary_tree_bfs.swift
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* Created Time: 2023-01-18
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* Author: nuomi1 (nuomi1@qq.com)
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*/
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import utils
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/* 层序遍历 */
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func levelOrder(root: TreeNode) -> [Int] {
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// 初始化队列，加入根节点
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var queue: [TreeNode] = [root]
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// 初始化一个列表，用于保存遍历序列
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var list: [Int] = []
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while !queue.isEmpty {
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let node = queue.removeFirst() // 队列出队
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list.append(node.val) // 保存节点值
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if let left = node.left {
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queue.append(left) // 左子节点入队
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}
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if let right = node.right {
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queue.append(right) // 右子节点入队
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}
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}
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return list
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}
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@main
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enum BinaryTreeBFS {
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/* Driver Code */
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static func main() {
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/* 初始化二叉树 */
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// 这里借助了一个从数组直接生成二叉树的函数
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let node = TreeNode.listToTree(arr: [1, 2, 3, 4, 5, 6, 7])!
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print("\n初始化二叉树\n")
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PrintUtil.printTree(root: node)
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/* 层序遍历 */
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let list = levelOrder(root: node)
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print("\n层序遍历的节点打印序列 = \(list)")
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}
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}
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