>>647
#include<stdio.h>

#define BUF_SIZE 1024

int main(void)
{
double a, b, x, y;
char buf[BUF_SIZE];
int scanf_ret;

printf("Input a, b:");
scanf("%lf %lf", &a, &b);
while(1)
{
printf("Input x:");
scanf("%s", buf);
scanf_ret=sscanf(buf, "%lf", &x);
if(scanf_ret!=1)
break;
y=a*x+b;
printf("y=a*x+b y=%f x=%f a=%f b=%f\n", y, x, a, b);
}

return 0;
}