29 lines
552 B
Go
29 lines
552 B
Go
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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 isValidSubBST(root *TreeNode, min, max int) bool {
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if root == nil {
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return true
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}
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if root.Val < min || root.Val > max {
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return false
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}
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return isValidSubBST(root.Left, min, root.Val-1) && isValidSubBST(root.Right, root.Val+1, max)
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}
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func isValidBST(root *TreeNode) bool {
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return isValidSubBST(root, -1<<31, 1<<31)
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}
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