#include "binary_tree.h" #include<bits/stdc++.h> void HierarchyOrder(BiTreeNode* root) // 二叉树的层次遍历（队列实现） // 参数：二叉树根节点root // 输出：二叉树的层次遍历，中间没有空格，末尾不换行。 { queue<BiTreeNode*>q; q.push(root); if(root==NULL)return; while(!q.empty()){ BiTreeNode*node=q.front(); q.pop(); cout<<node->data; if(node->left!=NULL){ q.push(node->left); } if(node->right!=NULL){ q.push(node->right); } } }以上代码用C语言表达怎么写

以下是使用 C 语言表达的二叉树层次遍历代码：

#include <stdio.h>
#include <stdlib.h>

typedef struct TreeNode {
    int data;
    struct TreeNode *left, *right;
} TreeNode;

typedef struct QueueNode {
    TreeNode *treeNode;
    struct QueueNode *next;
} QueueNode;

typedef struct {
    QueueNode *front, *rear;
} Queue;

Queue *createQueue() {
    Queue *q = (Queue *)malloc(sizeof(Queue));
    q->front = NULL;
    q->rear = NULL;
    return q;
}

int isQueueEmpty(Queue *q) {
    return q->front == NULL;
}

void enqueue(Queue *q, TreeNode *treeNode) {
    QueueNode *newNode = (QueueNode *)malloc(sizeof(QueueNode));
    newNode->treeNode = treeNode;
    newNode->next = NULL;
    if (isQueueEmpty(q)) {
        q->front = newNode;
    } else {
        q->rear->next = newNode;
    }
    q->rear = newNode;
}

TreeNode *dequeue(Queue *q) {
    if (isQueueEmpty(q)) {
        return NULL;
    }
    TreeNode *treeNode = q->front->treeNode;
    QueueNode *tempNode = q->front;
    q->front = q->front->next;
    if (q->front == NULL) {
        q->rear = NULL;
    }
    free(tempNode);
    return treeNode;
}

void levelOrder(TreeNode *root) {
    if (root == NULL) {
        return;
    }
    Queue *q = createQueue();
    enqueue(q, root);
    while (!isQueueEmpty(q)) {
        TreeNode *node = dequeue(q);
        printf("%d", node->data);
        if (node->left != NULL) {
            enqueue(q, node->left);
        }
        if (node->right != NULL) {
            enqueue(q, node->right);
        }
    }
}

int main() {
    // 构造一棵二叉树
    TreeNode *root = (TreeNode *)malloc(sizeof(TreeNode));
    root->data = 1;
    root->left = (TreeNode *)malloc(sizeof(TreeNode));
    root->left->data = 2;
    root->left->left = NULL;
    root->left->right = NULL;
    root->right = (TreeNode *)malloc(sizeof(TreeNode));
    root->right->data = 3;
    root->right->left = (TreeNode *)malloc(sizeof(TreeNode));
    root->right->left->data = 4;
    root->right->left->left = NULL;
    root->right->left->right = NULL;
    root->right->right = (TreeNode *)malloc(sizeof(TreeNode));
    root->right->right->data = 5;
    root->right->right->left = NULL;
    root->right->right->right = NULL;

    // 层次遍历
    levelOrder(root);

    return 0;
}

这段代码使用了队列的方式实现二叉树的层次遍历。首先定义了一个 Queue 结构体来实现队列的操作，其中包括了 enqueue、dequeue、isQueueEmpty 等基本操作。然后定义了一个 levelOrder 函数来进行层次遍历，其中也是使用队列来实现的。最后在主函数中构造了一棵二叉树，并进行层次遍历。