36 lines
634 B
Go
36 lines
634 B
Go
// Package q230 implements a solution for https://leetcode.com/problems/kth-smallest-element-in-a-bst/
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package q230
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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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func findKth(node *TreeNode, k, current int) (int, *int) {
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if node == nil {
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return current, nil
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}
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current, ret := findKth(node.Left, k, current)
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if ret != nil {
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return current, ret
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}
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current += 1
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if current == k {
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return current, &node.Val
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}
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return findKth(node.Right, k, current)
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}
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func kthSmallest(root *TreeNode, k int) int {
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_, kth := findKth(root, k, 0)
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if kth == nil {
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return 0
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}
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return *kth
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}
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var _ = kthSmallest
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