《 Skynet 游戏服务器开发实战》

#include <stdio.h>
#include <string.h>

int main()
{
    int m, n;
    int k = 0;
    int ticket[10001];
    while (scanf("%d %d", &m, &n))
    {
        int i = 1;
        if (!m && !n)
        {
            break;
        }
        memset(ticket, 0, sizeof(ticket));
        int tmp;
        for (i = 1; i <= n; i++)
        {
            scanf("%d", &tmp);
            ticket[tmp]++;
        }
        for (i = 1; i <= m; i++)
        {
            if (ticket[i] > 1)
            {
                k++;
            }
        }
        printf("%d\n", k);
    }
    return 0;
}