修改# include < malloc . h > typedef char ElemType ; typedef struct DataNode ElemType data ; struct DataNode * next , ] DataNode , typedef struct /／链队数据结点类型 DataNode * front , DataNode * rear ;] LinkQuNode ; void InitQueue ( LinkQuNode * q ) /／链队类型 q =( LinkQuNode *) malloc ( sizeof ( LinkQuNode )); g -> front = q -> rear = NULL ; void DestroyQueue ( LinkQuNode * q ) DataNode * p = q -> front .* x :// p 指向队头数捉结占节（ p != NULL ) /経放数据结点占用空间 r = p -/ next ; while ( r != NULL ) free ( p ); p = r , r = p -> next , free ( p ) free ( q ) /／释放链队结点占用空间 bool QueueEmpty ( LinkQuNode * q ) return ( q -) rear == NULL ); void enQueue ( LinkQuNode * q , ElemType e ) anaNode *) malloc ( sizeof ( DataNode )); p -> data = e , p -> next = NULL ; if ( q -/ rear == MULL ) else /／若链队为空，则新结点是队首结点又是队尾结点/／将 p 结点链到队尾，并将 rear 指向它 q -) front = q -) rear = p ; q -> rear -> next = p ; q -> rear = p ; bool deQueue ( LinkQuNode * q ElenType & e ) rear == NULL ) return false t = a 。 front 人列中只有一个结望问第一个数据结点 /／队列中有多个结点时 /／队列为空 else

修改后的代码如下：

#include <stdlib.h>
#include <stdbool.h>

typedef char ElemType;
typedef struct DataNode {
    ElemType data;
    struct DataNode *next;
} DataNode;

typedef struct {
    DataNode *front, *rear;
} LinkQuNode;

void InitQueue(LinkQuNode *q) {
    q = (LinkQuNode *) malloc(sizeof(LinkQuNode));
    q->front = q->rear = NULL;
}

void DestroyQueue(LinkQuNode *q) {
    DataNode *p = q->front;
    DataNode *r;

    while (p != NULL) {
        r = p->next;
        free(p);
        p = r;
    }

    free(q);
}

bool QueueEmpty(LinkQuNode *q) {
    return (q->rear == NULL);
}

void enQueue(LinkQuNode *q, ElemType e) {
    DataNode *p = (DataNode *) malloc(sizeof(DataNode));
    p->data = e;
    p->next = NULL;

    if (q->rear == NULL) {  // 若链队为空，则新结点是队首结点又是队尾结点
        q->front = q->rear = p;
    } else {
        q->rear->next = p;  // 将 p 结点链到队尾，并将 rear 指向它
        q->rear = p;
    }
}

bool deQueue(LinkQuNode *q, ElemType &e) {
    if (q->rear == NULL) {  // 队列为空
        return false;
    } else {
        DataNode *t = q->front;
        e = t->data;

        if (q->front == q->rear) {  // 队列中只有一个结点，第一个数据结点
            q->front = q->rear = NULL;
        } else {  // 队列中有多个结点时
            q->front = t->next;
        }

        free(t);
        return true;
    }
}