int n = 0; printf("请输入1-7的数,0退出\n"); scanf("%d", &n); switch (n) { case 0:printf("已退出\n");return 0; case 1:printf("星期%d\n", MONDAY); break; case 2:printf("星期%d\n", TUESDAY); break; case 3:printf("星期%d\n", WEDNESDAY); break; case 4:printf("星...