利用链表建立二叉树，完成前序遍历、中序遍历、后序遍历。
建立二叉树用的是前序遍历建立二叉树：
1 #include<stdio.h>
2 #include<stdlib.h>
3 #include<math.h>
4 #include<malloc.h>
5
6
7 typedef int element;
8 typedef struct Tree{
9 struct Tree *lchild,*rchild;
10 char data;
11 }*pTree,pNode;
12
13 //char str[]="ABD#E##FG###CI##H##";
14 char str[]="ABDH#K###E##CFI###G#J##";
15 element index=0;
16 //Init a empty tree
17 element Init_tree(pTree *T)
18 {
19 *T=NULL;
20 printf("init a empty tree\n");
21 }
22
23 //build a tree
24 void Creat_tree(pNode **T)
25 {
26 char num;
27 num=str[index++];
28 pTree P=NULL;
29 //P=*T;
30 if(num==‘#‘)
31 *T=NULL;
32 else
33 {
34 // if(!(*T))
35 // exit(OVERFLOW);
36 (*T)=(pTree)malloc(sizeof(pNode));
37 //memset(*T,0,sizeof(pNode));
38 (*T)->data=num;
39 Creat_tree(&(*T)->lchild);
40 Creat_tree(&(*T)->rchild);
41 }
42 }
43
44 //pro order traversal
45 element Pro_trav(pTree T)
46 {
47 if(T==NULL)
48 return ;
49 printf("pro order traversal data:%c\n",T->data);
50 Pro_trav(T->lchild);
51 Pro_trav(T->rchild);
52 }
53
54 //midle order traversal
55 element Mid_trav(pTree T)
56 {
57 if(T==NULL)
58 return;
59 Mid_trav(T->lchild);
60 printf("mid order traversal data:%c\n",T->data);
61 Mid_trav(T->rchild);
62 }
63
64 //after traversal
65 element Aft_trav(pTree T)
66 {
67 if(T==NULL)
68 return;
69 Aft_trav(T->lchild);
70 Aft_trav(T->rchild);
71 printf("after order traversal data:%c\n",T->data);
72 }
73
74 element main()
75 {
76 pTree T;
77 T=(pTree)malloc(sizeof(struct Tree));
78 //Init_tree(&T);
79 printf("before is ok\n");
80 Creat_tree(&T);
81 Pro_trav(T);
82 Mid_trav(T);
83 Aft_trav(T);
84 return 0;
85 }
86
输出结果：
1 before is ok 2 pro order traversal data:A 3 pro order traversal data:B 4 pro order traversal data:D 5 pro order traversal data:H 6 pro order traversal data:K 7 pro order traversal data:E 8 pro order traversal data:C 9 pro order traversal data:F 10 pro order traversal data:I 11 pro order traversal data:G 12 pro order traversal data:J 13 mid order traversal data:H 14 mid order traversal data:K 15 mid order traversal data:D 16 mid order traversal data:B 17 mid order traversal data:E 18 mid order traversal data:A 19 mid order traversal data:I 20 mid order traversal data:F 21 mid order traversal data:C 22 mid order traversal data:G 23 mid order traversal data:J 24 after order traversal data:K 25 after order traversal data:H 26 after order traversal data:D 27 after order traversal data:E 28 after order traversal data:B 29 after order traversal data:I 30 after order traversal data:F 31 after order traversal data:J 32 after order traversal data:G 33 after order traversal data:C 34 after order traversal data:A
时间： 2024-10-07 06:07:18