Codevs 二叉树遍历问题 合集

 1 #include<cstdio>
 2 #include<cstring>
 3 #include<iostream>
 4 using namespace std;
 5 int n,x,y;
 6 struct node{
 7     int left,right;
 8 }tree[256];
 9 void preorder(int k)
10 {
11     cout<<k<<‘ ‘;
12     if(tree[k].left!=0)
13       preorder(tree[k].left);
14     if(tree[k].right!=0)
15       preorder(tree[k].right);
16 }
17 void inorder(int k)
18 {
19     if(tree[k].left!=0)
20       inorder(tree[k].left);
21     cout<<k<<‘ ‘;
22     if(tree[k].right!=0)
23       inorder(tree[k].right);
24 }
25 void postorder(int k)
26 {
27     if(tree[k].left!=0)
28       postorder(tree[k].left);
29     if(tree[k].right!=0)
30       postorder(tree[k].right);
31     cout<<k<<‘ ‘;
32 }
33 int main()
34 {
35     scanf("%d",&n);
36     for(int i=1;i<=n;i++)
37     {
38         scanf("%d%d",&x,&y);
39         tree[i].left=x;tree[i].right=y;
40     }
41     preorder(1);// 前序遍历 
42     cout<<endl;
43     inorder(1);
44     cout<<endl;
45     postorder(1);
46     return 0;
47 }