import java.io.IOException;
import java.util.Scanner; // must have this to take in input (cin)
 
 
public class Main {
 
    public Main() {
    }
 
 
    public static void main(String[] args) throws IOException {
 
        // Create scanner variable (cin variable)
        Scanner scan = new Scanner(System.in);
 
        System.out.println("\nWelcome to the Interest Calculator");
 
        char decision = 'y';
 
        while (decision == 'y' || decision == 'Y')   // cin >> decision
        {
            System.out .println("\nEnter loan amount:   ");
            float loan = scan.nextFloat();
 
            System.out.println("Enter interest rate: ");
            float rate = scan.nextFloat();
 
            System.out.println("\nLoan amount:         $" + loan);
            System.out.println("Interest rate:       " + (rate*100) + "%");
 
            float interest = (loan*rate);
 
            System.out.println("Interest:            $" + interest);
 
            System.out.println("Continue? (y/n): ");
            decision = (char)System.in.read();
        }
    }
 
    public String alter(float n) {
        /// Pre: variable n must be of type float
        /// Post: return loan amount as a string with commas inserted
 
        String number = Float.toString(number); // ERROR HERE convert float to string;
 
        number.length();
 
        return number;
    }
 
}

String number = Float.toString(number);

String number = new Float(n).toString();

String number = String.valueOf(n);