I'm trying to make a greedy algorithm and I get this error:

greedy2.c:27:1: error: control reaches end of non-void function
      [-Werror,-Wreturn-type]
}
^
1 error generated.

with this code:

int man(int argc, char* argv[])
{

  float amount;
  do
    {
      printf("Input dollar amount owed:\n");
      amount = GetFloat();
    }
  while (amount <= 0);    
  int coins = 0;
  while (amount >= 0.25);
  {
    amount = amount - 0.25;
    coins++;
  }
  printf("Number of coins to use: %d\n", coins);

}

What is wrong with my curly braces, and how do I fix it?