1. #include<stdio.h>
    2. #include<stdlib.h>
    3. typedef struct BiTNode{
    4.     char data;
    5.     struct BiTNode *L;
    6.     struct BiTNode *R;
    7. }BiTNode,*BiTree;
    8. //前序创建二叉树
    9. void PreCreatBiTree(BiTree*t);
    10. //前序遍历二叉树
    11. void PreShowBiTree(BiTree  t);
    12. //中序遍历二叉树
    13. void MidShowBiTree(BiTree t);
    14. //后序遍历二叉树
    15. void RearShowBiTree(BiTree t);
    16. int main(){
    17. //定义二叉树
    18. BiTree t;
    19. printf("请输入任意字符，#代表空\n");
    20. PreCreatBiTree(&t);
    21. printf("前序遍历结果为：\n");
    22. PreShowBiTree(t);
    23. printf("\n");
    24. printf("中序遍历结果为：\n");
    25. MidShowBiTree(t);
    26. printf("\n");
    27. printf("后序遍历结果为:\n");
    28. RearShowBiTree(t);
    29. printf("\n");
    30. }
    31. void PreCreatBiTree(BiTree*t){
    32.     char ch;
    33.     scanf("%c",&ch);
    34.     if(ch == '#')
    35.     {
    36.         *t = NULL;
    37.     }
    38.     else 
    39.     {
    40.         *t = (BiTree)malloc(sizeof(BiTNode));
    41.         if(NULL == (*t))return;
    42.         (*t) -> data = ch;
    43.         PreCreatBiTree(&(*t)->L);
    44.         PreCreatBiTree(&(*t)->R);
    45.     }
    47. }
    48. void PreShowBiTree(BiTree t){
    49.     if(t != NULL)
    50.     {
    51.         printf("%c",t->data);
    52.         PreShowBiTree(t->L);
    53.         PreShowBiTree(t->R);
    54.     }
    55. }
    56. void MidShowBiTree(BiTree t){
    57.     if(t != NULL)
    58.     {
    59.         MidShowBiTree(t->L);
    60.         printf("%c",t ->data);
    61.         MidShowBiTree(t->R);
    62.     }
    63. }
    64. void RearShowBiTree(BiTree t){
    65.     if(t != NULL)
    66.     {
    67.         RearShowBiTree(t->L);
    68.         RearShowBiTree(t->R);
    69.         printf("%c",t->data);
    70.     }
    71. }