隊列實例代碼（C語言）

隊列實例代碼(C語言)，具體的實現如下代碼所示：

QueueDemo.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdbool.h>
#define MAX 6

int intArray[MAX];
int front = 0;
int rear = -1;
int itemCount = 0;

int peek(){
return intArray[front];
}

bool isEmpty(){
return itemCount == 0;
}

bool isFull(){
return itemCount == MAX;
}

int size() {
return itemCount;
}

void insert(int data){

if(!isFull()){
if(rear == MAX-1){
rear = -1;
}

  intArray\[++rear\] = data;
  itemCount++;

}
}

int removeData(){
int data = intArray[front++];

if(front == MAX){
front = 0;
}

itemCount--;
return data;
}

int main() {
/* insert 5 items */
insert(3);
insert(5);
insert(9);
insert(1);
insert(12);

// front : 0
// rear : 4
// ------------------
// index : 0 1 2 3 4
// ------------------
// queue : 3 5 9 1 12
insert(15);

// front : 0
// rear : 5
// ---------------------
// index : 0 1 2 3 4 5
// ---------------------
// queue : 3 5 9 1 12 15

if(isFull()){
printf("Queue is full!\n");
}

// remove one item
int num = removeData();

printf("Element removed: %d\n",num);
// front : 1
// rear : 5
// -------------------
// index : 1 2 3 4 5
// -------------------
// queue : 5 9 1 12 15

// insert more items
insert(16);

// front : 1
// rear : -1
// ----------------------
// index : 0 1 2 3 4 5
// ----------------------
// queue : 16 5 9 1 12 15

// As queue is full, elements will not be inserted.
insert(17);
insert(18);

// ----------------------
// index : 0 1 2 3 4 5
// ----------------------
// queue : 16 5 9 1 12 15
printf("Element at front: %d\n",peek());

printf("----------------------\n");
printf("index : 5 4 3 2 1 0\n");
printf("----------------------\n");
printf("Queue: ");

while(!isEmpty()){
int n = removeData();
printf("%d ",n);
}
}

如果我們編譯並運行上述程序那麼這將產生以下結果 -

Queue is full!
Element removed: 3
Element at front: 5

---

index : 5 4 3 2 1 0

Queue: 5 9 1 12 15 16