3-31树的练习||

建立排序树


#include<stdio.h>
struct node
{
    node *lchild;
    node *rchild;
    int r;
}tree[102];
int loc;
node *create()
{
    tree[loc].lchild = tree[loc].rchild = NULL;
    return &tree[loc ++];
}
void *build(int x,node *t)
{
    node *q = t;
    node *p = create();
    p -> r = x;
    while(q -> rchild != NULL || q -> lchild != NULL)
    {
        while(q -> r <= x && q -> rchild != NULL)
            q = q ->rchild;
        while(q -> r >= x && q -> lchild != NULL)
            q = q -> lchild;
        if(q -> lchild != NULL && q ->r <= x)
            break;
        if(q -> rchild != NULL && q -> r >= x)
            break;
    }
    if(q -> r <= x)
    {
        q -> rchild = p;
    }
    else
    {
        q -> lchild = p;
    }
}
void preorder(node *p)
{
    printf("%d ",p -> r);
    if(p -> lchild != NULL)
        preorder(p -> lchild);
    if(p -> rchild != NULL)
        preorder(p -> rchild);
}
void inorder(node *p)
{
    if(p -> lchild != NULL)
        inorder(p -> lchild);
    printf("%d ",p -> r);
    if(p -> rchild != NULL)
        inorder(p -> rchild);
}
void postorder(node *p)
{
    if(p -> lchild != NULL)
        postorder(p -> lchild);
    if(p -> rchild != NULL)
        postorder(p -> rchild);
    printf("%d ",p -> r);
}
int main()
{
    int n;
    while(scanf("%d",&n) != EOF)
    {
        int x;
        loc  = 0;
        node *t;
        scanf("%d",&x);
        t = create();
        t -> r = x;
        for(int i = 1; i != n ; i ++)
        {
            scanf("%d",&x);
            build(x,t);
        }
        preorder(t);
        printf("\n");
        inorder(t);
        printf("\n");
        postorder(t);
        printf("\n");
    }
    return 0;
}