39 lines
712 B
Go
39 lines
712 B
Go
package main
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type TreeNode struct {
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Val int
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Left *TreeNode
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Right *TreeNode
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}
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/**
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* Definition for a binary tree node.
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* type TreeNode struct {
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* Val int
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* Left *TreeNode
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* Right *TreeNode
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* }
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*/
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func isSymmetric(root *TreeNode) bool {
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if root == nil {
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return true
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}
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queue := []*TreeNode{root}
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for len(queue) != 0 {
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l := len(queue)
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current := queue
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queue = queue[l:]
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for idx, node := range current {
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if (node == nil && current[l-idx-1] != nil) ||
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(node != nil && current[l-idx-1] == nil) ||
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(node != nil && node.Val != current[l-idx-1].Val) {
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return false
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}
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if node != nil {
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queue = append(queue, node.Left, node.Right)
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}
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}
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}
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return true
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}
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