C PRIMER PLUS 第六版 第八章 程序清单8.8

C PRIMER PLUS 第六版 第八章 程序清单8.8

我这个代码和书上运行的结果不一样 不知道哪里错了，谁能帮忙解答下
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
char get_first(void);
char get_second(void);
void count(void);
int get_three(void);
int main(void)
{
int ch;

while ((ch = get_first()) != 'q');
{
	switch (ch)
	{
	     case 'a': printf("buy low****high\n");
		           break;
	     case 'b': putchar('\a');
		           break;
	     case 'c': count();
		           break;
	     default:  printf("programe error\n");
		           break;
	}
}
return 0;

}
char get_first(void)
{
int ch;

printf("enter your choice\n");
printf("a.advice         b.bell\n");
printf("c.count          d.quit\n");
ch = get_second();
while ((ch<'a' || ch>'c') && ch != 'q')
{
	printf("please responds with a b c\n");
	ch = get_second();
}
return ch;

}
char get_second(void)
{
int ch;

ch = getchar();
while (getchar() != '\n')
	continue;

return ch;

}
void count(void)
{
int i, n;

printf("count how far?\n");
n = get_three();
for (i = 1; 1 <= n; i++)
	printf("%d\n", i);
while (getchar() != '\n')
	continue;

}
int get_three(void)
{
int num;
char ch;

while (scanf("%d", &num) != 1)
{
	while ((ch = getchar()) != '\n')
		putchar(ch);
	printf("这不是整数 重新输入\n");
}
return num;

}