数据结构之队列（C语言）

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

typedef struct node{
   int  data;
   struct node *next;
}NODE;

typedef struct qnode{
   NODE *front;
   NODE *rear;
}QNODE;

   void InitQueue(QNODE *Q){
  NODE *p;
  p=(NODE *)malloc(sizeof(NODE));
  Q->front=p;
  Q->front->next=NULL;
  Q->rear=Q->front;
  printf("The init is complete!");

}
   void *QueuePush(QNODE *Q){
  NODE *p;   p=(NODE *)malloc(sizeof(NODE));
  printf("Please input a number :");
  scanf("%d",&p->data);
  p->next=NULL;
  Q->rear->next=p;
  Q->rear=p;
  printf("The %d has been pushed into the Queue!",p->data);
  return 0;
}
   void *QueuePop(QNODE *Q){
  NODE *p;
  if(Q->front->next==NULL) return 0;
  p=Q->front->next;
  Q->front->next=p->next;
  if(Q->rear==p) Q->rear=Q->front;
  printf("The %d has been pop from the queue! /n",p->data);
  free(p);
  return 0;
}
   void *PrintQueue(QNODE *Q){
  NODE *p;
  p=Q->front->next;
  while(p!=NULL){
  printf("%5d",p->data);
  p=p->next;}
  return 0;
}

   void main(){
  QNODE *T;
  int i=0;
  printf("1.InitQueue 2.QueuePush 3.QueuePop 4.PrintQueue 5.Quit /n");
  while(i!=5){
  printf("Please choose the gongneng:");
  scanf("%d",&i);
  printf("/n");
  switch(i){
  case 1: InitQueue(T); printf("/n"); break;
  case 2: QueuePush(T);  printf("/n"); break;
  case 3: QueuePop(T);   printf("/n"); break;
  case 4: printf("The queue's numbers are:");
    PrintQueue(T);  printf("/n"); break;
  case 5:  printf("/n"); break;}
  }
}