42 lines
953 B
Go
42 lines
953 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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func main() {
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}
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func pathSum(root *TreeNode, targetSum int) int {
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if root == nil {
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return 0
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}
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if root.Left == nil && root.Right == nil && root.Val == targetSum {
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return 1
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}
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hash := make(map[int]int)
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var culcalute func(root *TreeNode, hash map[int]int, total int, targetSum int) int
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culcalute = func(roottmp *TreeNode, hash map[int]int, total int, targetSum int) int {
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if roottmp == nil {
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return 0
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}
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restmp := 0
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hashtmp := make(map[int]int)
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for k, v := range hash {
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hashtmp[k] = v
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}
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totalnum := total + roottmp.Val
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if value, ok := hash[totalnum-targetSum]; ok {
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restmp = restmp + value
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}
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hashtmp[totalnum]++
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res := culcalute(roottmp.Left, hashtmp, totalnum, targetSum) + culcalute(roottmp.Right, hashtmp, totalnum, targetSum) + restmp
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return res
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}
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hash[0]++
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result := culcalute(root, hash, 0, targetSum)
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return result
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}
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