text: #include<stdio.h>
  #include<ctype.h>
  #include<cs50.h>
  #include<math.h>
  int main(void)
  {
      int nickel=0,quarter=0, penny=0, dime=0, amount=0;
      float change;
      
      do
      {
          printf("how much change is owed?");
          change=GetFloat();
          if(isalpha(change))
          {
              printf("retry");
              change=GetFloat();
          }
      }while(change<0);
      
      amount= (round(change*100));  
      
      quarter= amount/25;
      amount=amount%25;   
      
      nickel = amount/10;
      amount = amount%10;
      
      dime = amount/5;
      amount = amount%5;
      
      penny = amount/1;
      amount=amount%1;
      
      printf("%d\n", (quarter+nickel+penny+dime));
      return 0;
  }
  