队列（ FIFO ） 循环队列

队列（ FIFO ）

数组实现

#include <stdio.h>
#define N 64
int main()
{
    int i, n, front, rear, q[2*N];
    scanf("%d", &n);
    for(i = 0; i < n; i++)
        q[i] = i + 1;
    front = 0;
    rear = n;
    while(rear – front > 0)
    {
        printf("%d ", q[front]);
        front++;
        q[rear++] = q[front++];
    }
    return 0;
}

循环队列

数组实现

#include <stdio.h>
#define N 64
int main()
{
     int i, n, front, rear, q[N];
     scanf("%d", &n);
     for(i = 0; i < n; i++)
         q[i] = i + 1;
     front = 0;   rear = n;
     while((rear - front + N) % N > 0)
     {
         printf("%d ", q[front]);
         front = (front + 1) % N;
         q[rear] = q[front];
         rear = (rear + 1) % N;
         front = (front + 1) % N;
     }
     return 0;
}

STL实现

#include <cstdio>
#include <queue>
using namespace std;
int main()
{
    queue<int> q;
    int i, n;
    scanf("%d", &n);
    for(i = 0; i < n; i++)
        q.push(i + 1);
    while(!q.empty())
    {
        printf("%d ", q.front());
        q.pop();
        q.push(q.front());
        q.pop();
    }
    return 0;
}