95 lines
1.5 KiB
Go
95 lines
1.5 KiB
Go
package binarytree
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import (
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"fmt"
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"testing"
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"github.com/stretchr/testify/assert"
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)
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var tcs = []struct {
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pre, in, post []int
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}{
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{
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[]int{1, 2, 3},
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[]int{1, 3, 2},
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[]int{3, 2, 1},
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},
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{
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[]int{1, 2, 4, 5, 3, 6, 7},
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[]int{4, 2, 5, 1, 6, 3, 7},
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[]int{4, 5, 2, 6, 7, 3, 1},
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},
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// 可以有多个 testCase
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}
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func PreIn2Tree(pre, in []int) *TreeNode {
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if len(pre) != len(in) {
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panic("preIn2Tree 中两个切片的长度不相等")
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}
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if len(in) == 0 {
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return nil
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}
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res := &TreeNode{
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Val: pre[0],
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}
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if len(in) == 1 {
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return res
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}
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idx := indexOf(res.Val, in)
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res.Left = PreIn2Tree(pre[1:idx+1], in[:idx])
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res.Right = PreIn2Tree(pre[idx+1:], in[idx+1:])
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return res
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}
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func indexOf(val int, nums []int) int {
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for i, v := range nums {
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if v == val {
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return i
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}
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}
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return 0
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}
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func Test_preOrderTraversal(t *testing.T) {
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ast := assert.New(t)
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for _, tc := range tcs {
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fmt.Printf("~~%v~~\n", tc)
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root := PreIn2Tree(tc.pre, tc.in)
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ast.Equal(tc.pre, preOrderTraversal(root), "输入:%v", tc)
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}
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}
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func Test_inOrderTraversal(t *testing.T) {
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ast := assert.New(t)
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for _, tc := range tcs {
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fmt.Printf("~~%v~~\n", tc)
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root := PreIn2Tree(tc.pre, tc.in)
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ast.Equal(tc.in, inOrderTraversal(root), "输入:%v", tc)
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}
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}
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func Test_postOrderTraversal(t *testing.T) {
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ast := assert.New(t)
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for _, tc := range tcs {
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fmt.Printf("~~%v~~\n", tc)
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root := PreIn2Tree(tc.pre, tc.in)
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ast.Equal(tc.post, postOrderTraversal(root), "输入:%v", tc)
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}
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}
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