#include <stdio.h>
#include <time.h>
int main ()
{
    time_t t;
    struct tm * lt;
    time (&t);
    lt = localtime (&t);
    printf ( "现在是：%d/%d/%d %d:%d:%d\n",lt->tm_year+1900, lt->tm_mon+2, lt->tm_mday, lt->tm_hour, lt->tm_min, lt->tm_sec);
    if(lt->tm_mon+1>0&&lt->tm_mon+1<5)
    printf("\n夜深了，该睡了");
    return 0;
}