二叉树编程模型


#include <stdio.h>

#include <stdlib.h>

#include <string.h>

typedef struct _bitree

{

char data;

struct _bitree *lchild,*rchild;

}*BiTree,BiTNode;

BiTree bitree_create(BiTree tree);

void prev_display(BiTree tree);

void midl_display(BiTree tree);

void last_display(BiTree tree);

//建立二叉树

BiTree bitree_create(BiTree tree)

{

char ch = getchar();

if(ch == '#')

tree = NULL;

else

{

tree = (BiTNode *)malloc(sizeof(BiTNode));

if(tree == NULL )

{

printf("creat error!\n");

return;

}

tree->data = ch;

tree->lchild = bitree_create(tree->lchild);

tree->rchild = bitree_create(tree->rchild);

}

return tree;

}

//先序遍历

//中，左，右

void prev_display(BiTree tree)

{

if(tree != NULL)

{

printf("%c ",tree->data);

prev_display(tree->lchild);

prev_display(tree->rchild);

}

}

//中序遍历

//左，中，右

void midl_display(BiTree tree)

{

if(tree != NULL)

{

prev_display(tree->lchild);

printf("%c ",tree->data);

prev_display(tree->rchild);

}

}

//后序遍历

//左，右，中

void last_display(BiTree tree)

{

if(tree != NULL)

{

prev_display(tree->lchild);

prev_display(tree->rchild);

printf("%c ",tree->data);

}

}

//求深度

int main()

{

BiTree tree = bitree_create(tree);

prev_display(tree);

printf("\n");

midl_display(tree);

printf("\n");

last_display(tree);

printf("\n");

return 0;

}