#include <stdio.h>
#include <malloc.h>
struct node{
    int data;
    struct node *next;
};
struct queuenode{
    struct node *front;
    struct node *rear;
};
struct queuenode *init(struct queuenode *s){
    s=(struct queuenode *)malloc(sizeof(struct queuenode));
    s->rear=(struct node *)malloc(sizeof(struct node));
    s->front=(struct node *)malloc(sizeof(struct node));
    s->rear->next=NULL;
    s->front=s->rear;
    return s;
}
int empty(struct queuenode *s){
    if(s->front==s->rear)
        return 1;
    else
        return 0;
}
void in_queue(struct queuenode *s,int n){
    struct node *p;
    p=(struct node *)malloc(sizeof(struct node));
    p->data=n;
    p->next=s->rear->next;
    s->rear=p;
}
int out_queue(struct queuenode *s){
    struct node *p;
    int e;
    if(empty(s)){
        printf("空队!");
        return -1;
    }
    else{
        p=s->front->next;//printf("%d",p->data);
        e=p->data;
        s->front->next=p->next;
        free(p);
        return e;
    }
}
void main(){
    struct queuenode *s;
    int i;
    s=init(s);
    for(i=0;i<5;i++)
        in_queue(s,i);
    //printf("%d",s->rear->data);
    while(!empty(s)){
        printf("%3d",out_queue(s));
    }
}

     s->rear=(struct node *)malloc(sizeof(struct node));
     s->front=(struct node *)malloc(sizeof(struct node));
没见过这么写的，找个案例好好看看吧

同求，错哪了？