2024.02.07作业

请编程实现二叉树的操作
1.二叉树的创建

typedef struct a
{
    char data;
    struct a* lchild;
    struct a* rchild;    
} *Node;

Node create_node()
{
    Node node = (Node)malloc(sizeof(struct a));
    if (NULL == node)
    {
        return NULL;
    }

    node->lchild = NULL;
    node->rchild = NULL;
    return node;
}

Node create_tree()
{
    char c;
    printf("请输入数据：");
    scanf("%c", &c);
    getchar();

    if ('#' == c)
    {
        return NULL;
    }

    Node node = create_node();
    if (NULL == node)
    {
        return NULL;
    }
    node->data = c;

    node->lchild = create_tree();
    node->rchild = create_tree();

    return node;
}

2.二叉树的先序遍历

void pre_order(Node root)
{
    if (NULL == root)
    {
        return;
    }

    printf("%2c", root->data);
    pre_order(root->lchild);
    pre_order(root->rchild);
}

3.二叉树的中序遍历

void in_order(Node root)
{
    if (NULL == root)
    {
        return;
    }

    in_order(root->lchild);
    printf("%2c", root->data);
    in_order(root->rchild);
}

4.二叉树的后序遍历

void post_order(Node root)
{
    if (NULL == root)
    {
        return;
    }

    post_order(root->lchild);
    post_order(root->rchild);
    printf("%2c", root->data);
}

5.二叉树各个节点度的个数

void count(Node root, int* n0, int* n1, int* n2)
{
    if (NULL == root)
    {
        return;
    }

    if (root->lchild && root->rchild)
    {
        (*n2)++;
    }
    else if (!root->lchild && !root->rchild)
    {
        (*n0)++;
    }
    else
    {
        (*n1)++;
    }

    count(root->lchild, n0, n1, n2);
    count(root->rchild, n0, n1, n2);
}

6.二叉树的深度

int height(Node root)
{
    if (NULL == root)
    {
        return 0;
    }

    int l = height(root->lchild);
    int r = height(root->rchild);

    return l > r ? l + 1 : r + 1;
}

结果

源代码

#include 
#include 

typedef struct a
{
    char data;
    struct a* lchild;
    struct a* rchild;    
} *Node;

Node create_node()
{
    Node node = (Node)malloc(sizeof(struct a));
    if (NULL == node)
    {
        return NULL;
    }

    node->lchild = NULL;
    node->rchild = NULL;
    return node;
}

Node create_tree()
{
    char c;
    printf("请输入数据：");
    scanf("%c", &c);
    getchar();

    if ('#' == c)
    {
        return NULL;
    }

    Node node = create_node();
    if (NULL == node)
    {
        return NULL;
    }
    node->data = c;

    node->lchild = create_tree();
    node->rchild = create_tree();

    return node;
}

void pre_order(Node root)
{
    if (NULL == root)
    {
        return;
    }

    printf("%2c", root->data);
    pre_order(root->lchild);
    pre_order(root->rchild);
}

void in_order(Node root)
{
    if (NULL == root)
    {
        return;
    }

    in_order(root->lchild);
    printf("%2c", root->data);
    in_order(root->rchild);
}

void post_order(Node root)
{
    if (NULL == root)
    {
        return;
    }

    post_order(root->lchild);
    post_order(root->rchild);
    printf("%2c", root->data);
}

void count(Node root, int* n0, int* n1, int* n2)
{
    if (NULL == root)
    {
        return;
    }

    if (root->lchild && root->rchild)
    {
        (*n2)++;
    }
    else if (!root->lchild && !root->rchild)
    {
        (*n0)++;
    }
    else
    {
        (*n1)++;
    }

    count(root->lchild, n0, n1, n2);
    count(root->rchild, n0, n1, n2);
}

int height(Node root)
{
    if (NULL == root)
    {
        return 0;
    }

    int l = height(root->lchild);
    int r = height(root->rchild);

    return l > r ? l + 1 : r + 1;
}

int main()
{
    Node root = create_tree();
    
    printf("先序：");
    pre_order(root);
    puts("");

    printf("中序：");
    in_order(root);
    puts("");

    printf("后序：");
    post_order(root);
    puts("");

    int n0 = 0, n1= 0, n2 = 0;
    count(root, &n0, &n1, &n2);
    printf("n0 = %d, n1 = %d, n2 = %d\n", n0, n1, n2);

    printf("高度：%d\n", height(root));

    return 0;
}