链队列

#include <stdio.h>
#include <malloc.h>

typedef struct Node{
    int data;
    struct Node* next;
}Node;

typedef struct Link{
    struct Node* rear;
    struct Node* front;
}Link;

int init(Link* L){
    L->front = (Node*)malloc(sizeof(Node));
    if(L->front != NULL)
    {
        L->rear = L->front;
        L->front->next = NULL;
        return 1;
    }
    return 0;
}

int Enter(Link* L, int x){
    Node* NewNode;
    NewNode = (Node*)malloc(sizeof(Node));
    if(NewNode != NULL)
    {
        NewNode->data = x;
        NewNode->next = NULL;
        L->rear->next = NewNode;
        L->rear = NewNode;
        return 1;
    }
    else return 0;
}
int Delete(Link* L, int* x){
    Node* r;
    r = L->front->next;
    if(r == NULL)      //或L->front == L->rear
        return 0;
    *x = r->data;
    L->front->next = r->next;
    if(L->rear == r)
        L->rear = L->front;
    free(r);
    return 1;
}

int main(){
    Link L;
    int x;
    init(&L);
    Enter(&L, 1);
    Enter(&L, 2);
    Enter(&L, 3);
    Delete(&L, &x);
    printf("%d\n", x);
    Delete(&L, &x);
    printf("%d\n", x);
    Delete(&L, &x);
    printf("%d\n", x);
    return 0;
}