#include <stdio.h>

int main(void)
{
  float commission, value;

  printf("Enter value of trade: ");
  scanf("%f", &value);

  while (value != 0.0) {
    if (value < 2500.00)
      commission = 30.00 + .017 * value;
    else if (value < 6250.00)
      commission = 56.00 + .0066 * value;
    else if (value < 20000.00)
      commission = 76.00 + .0034 * value;
    else if (value < 50000.00)
      commission = 100.00 + .0022 * value;
    else if (value < 500000.00)
      commission = 155.00 + .0011 * value;
    else
      commission = 255.00 + .0009 * value;

    if (commission < 39.00)
      commission = 39.00;

    printf("Commission: $%.2f\n\n", commission);

    printf("Enter value of trade: ");
    scanf("%f", &value);
  }

  return 0;
}