树结构练习——排序二叉树的中序遍历（二叉搜索树）

#include <stdio.h>
#include <stdlib.h>
typedef struct node
{
    int data;
    struct node *lchild;
    struct node *rchild;
}Tree;
int i, n, key, cnt = 0;
Tree *Insert(Tree *t , int key)
{
    if(t == NULL)
    {
        Tree *p;
        p = (Tree *)malloc(sizeof(Tree));
        p->data = key;
        p->lchild = NULL;
        p->rchild = NULL;
        t = p;
    }
    else
    {
        if(key < t->data)
            t->lchild = Insert(t->lchild, key);
        else
            t->rchild = Insert(t->rchild, key);
    }
    return t;
}

void InOrder(Tree *t)
{
    if(t!=NULL)
    {
        InOrder(t->lchild);

        cnt++;
        if(cnt==n)
             printf("%d\n", t->data);
        else
            printf("%d ", t->data);

        InOrder(t->rchild);
    }
}

int main()
{
    while(~scanf("%d", &n))
    {
        Tree * t = NULL;
        cnt = 0;
        for(i=0; i<n; i++)
        {
            scanf("%d", &key);
            t = Insert(t, key);
        }
        InOrder(t);
    }
    return 0;
}