Prata chapter 7 exs 11(not working!)

//prata exs chapter 7 number 11 - not working!

#include <stdio.h>
#include <ctype.h>
#define APRICE  2.05
#define BPRICE 1.15
#define CPRICE 1.09
#define CUTOFF3 29750.0
#define CUTOFF4 24750.0


int main()
{

    char ch;
    float a,b,c,temp;
    a=b=c=0.0;
    ch = getchar();

    while( ch !='q')
    {
        //a=b=c=temp = 0.0;//new order can do this  4 lines up
        printf("How much of it do you want?\n");
            scanf("%f",&temp);
        switch(ch)
        {
            case 'a':
                {
                   a+=temp;
                }
                break;
            case 'b':
                {
                   b+=temp;
                }
                break;
            case 'c':
                {
                    c+=temp;
                }
                break;
        }//end of switch()
        printf("so its' %f of a, %f of b, %f of c\n",a,b,c);//for some reason it goes straight to the top of
        //while() from here. ***WHY is that? I started from proper getchar() in while, for some reason it ignores all
        //getchar() except first one!
        //printf("boo\n");
        printf("what are you ordering now? a/b/c/q- quit\n");
        ch = getchar();
    }//end of while

    return 0;
}