l链队基本操作

_02.栈与队列/_f.链队列.c

@@ -3,6 +3,7 @@
 #include "io.h"
 
 #define MAXSIZE 20
+#define OVERFLOW -1
 #define OK 1
 #define ERROR 0
 #define TRUE 1
@@ -33,13 +34,13 @@ Status InitQueue(LinkQueue *Q)
     Q->front = Q->rear = (QueuePtr)malloc(sizeof(QNode));
     if (!Q->front)
     {
-        exit(-1);
+        exit(OVERFLOW);
     }
     Q->front->next = NULL;
     return OK;
 }
 
-Status Destroy(LinkQueue *Q)
+Status DestroyQueue(LinkQueue *Q)
 {
     while (Q->front)
     {
@@ -101,6 +102,77 @@ Status GetHead(LinkQueue Q, ElemType *e)
     return OK;
 }
 
-Status EnQueue(LinkQueue *Q,ElemType e){
+Status EnQueue(LinkQueue *Q, ElemType e)
-    Q
+{
+    QueuePtr p = (QueuePtr)malloc(sizeof(QNode));
+    if (!p)
+    {
+        exit(OVERFLOW);
+    }
+    p->data = e;
+    p->next = NULL;
+    Q->rear->next = p; //添加到链尾
+    Q->rear = p;
+    return OK;
+}
+
+Status DeQueue(LinkQueue *Q, ElemType *e)
+{
+    if (Q->rear == Q->front)
+    {
+        return ERROR;
+    }
+    QueuePtr p = Q->front->next;
+    *e = p->data;
+    Q->front->next = p->next;
+    if (Q->rear == p)
+    {
+        // 若链表除头节点外只剩下一个元素时，则需将rear指向头节点
+        //若队头就是队尾，则删除后将rear指向front
+        Q->rear = Q->front;
+    }
+    free(p);
+    return OK;
+}
+
+Status QueueTraverse(LinkQueue Q)
+{
+    QueuePtr p;
+    p = Q.front->next;
+    while (p)
+    {
+        visit(p->data);
+        p = p->next;
+    }
+    printf("\n");
+    return OK;
+}
+
+int main()
+{
+    ElemType e;
+    LinkQueue q;
+    int i = InitQueue(&q);
+    if (i)
+    {
+        printf("inited! \n");
+        printf("是否空队列？", QueueEmpty(q));
+    }
+    EnQueue(&q, -5);
+    EnQueue(&q, 5);
+    EnQueue(&q, 10);
+    printf("插入3个元素(-5,5,10)后,队列的长度为%d\n", QueueLength(q));
+    QueueTraverse(q);
+    i = GetHead(q, &e);
+    if (i == OK)
+        printf("队头元素是：%d\n", e);
+    DeQueue(&q, &e);
+    printf("删除了队头元素%d\n", e);
+    QueueTraverse(q);
+    ClearQueue(&q);
+	printf("清空队列后,q.front=%u q.rear=%u q.front->next=%u\n",q.front,q.rear,q.front->next);
+	DestroyQueue(&q);
+	printf("销毁队列后,q.front=%u q.rear=%u\n",q.front, q.rear);
+    getchar();
+
 }