我與代碼的日常：隊列的基本操作（C語言版）

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

typedef int QDataType;
 //鏈表節點
typedef struct QNode
{
	QDataType val;
	struct QNode* next;
}QNode;

//隊列
typedef struct Queue
{
	QNode* front; //指向隊首元素
	QNode* rear; //指向隊尾元素
	int size;
} Queue;

//初始化
void QueueInit(Queue* queue)
{
	queue->front = queue->rear = NULL;
	queue->size = 0;
	printf("隊列初始化成功!\n");
}

//銷燬
void QueueDestroy(Queue* queue)
{
	QNode* next;
	for (QNode*cur = queue->front; cur != NULL; cur = next)
	{
		next = cur->next;
		free(cur);
	}
	queue->front = queue->rear = NULL;
	queue->size = 0;
	printf("銷燬成功!\n");
}

//增加元素
void QueuePush(Queue* queue, QDataType val)
{
	QNode* node = (QNode*)malloc(sizeof(QNode));
	node->val = val;
	node->next = NULL;
	queue->size++;
	if (queue->rear == NULL)
	{
		//隊列起初爲空
		queue->front = queue->rear = node;
	}
	else
	{
		queue->rear ->next= node;
		queue->rear = node;
		queue->rear->next = NULL; 
	}
	printf("%d入隊成功!\n", node->val);
}

//刪除
void QueuePop(Queue* queue)
{
	assert(queue->size > 0);
	queue->size--;
	QNode* old_front = queue->front;
	queue->front = queue->front->next;
	free(old_front);
	if (queue->front == NULL)
	{
		printf("隊列爲空，刪除失敗!\n");
	}
}

//返回隊首元素
QDataType QueueFront(Queue* queue)
{
	assert(queue->size > 0);
	return queue->front->val;
}

//返回隊列元素個數
int QueueSize(Queue* queue)
{
	return queue->size;
}

//打印隊列元素
void QueuePrint(Queue* queue)
{
	assert(queue->size > 0);
	QNode* cur = queue->front;
	while (cur!=NULL)
	{
		printf("%d  ", cur->val);
		cur = cur->next;
	}
}

void Test()
{
	Queue queue;
	QueueInit(&queue);
	QueuePush(&queue, 1);
	QueuePush(&queue, 2);
	QueuePush(&queue, 3);
	QueuePush(&queue, 4);
	QueuePush(&queue, 5);
	QueuePrint(&queue);
	printf("\n刪除一個元素: ");
	QueuePop(&queue);
	QueuePrint(&queue);
	printf("此時隊首元素爲: %d\n", QueueFront(&queue));
	printf("\n此時隊列裏元素個數爲: %d\n", QueueSize(&queue));
	QueueDestroy(&queue);
}

int main()
{
	Test();
	system("pause");
	return 0;
}

運行結果：