672 税
#include <stdio.h>
int main()
{
double x;
scanf("%lf", &x);
if (x > 0.00 && x < 2000.00)
printf("Isento\n");
else
{
double tax;
if (x <= 3000)
{
tax = (x - 2000) * 0.08;
printf("R$ %.2lf", tax);
}
else if (x > 3000 && x <= 4500)
{
tax = 1000 * 0.08 + (x - 3000) * 0.18;
printf("R$ %.2lf", tax);
}
else
{
tax = 1000 * 0.08 + 1500 * 0.18 + (x - 4500) * 0.28;
printf("R$ %.2lf", tax);
}
}
return 0;
}