Question

The user will input a dollar amount as a floating point number; read it from input using a Scanner and the .nextDouble() method. Convert the number of dollars into a number of whole (integer) cents, e.g., $1.29 = 129 cents. Determine and output the optimal number of quarters, dimes, nickels, and pennies used to make that number of cents.

Ex: if the input is

1.18

The output should be

4
1
1
3

for 4 quarters, 1 dime, 1 nickel, 3 pennies.

Hints

1. Remember that a double multiplied by an int gives back a double. You will need to cast the result to int if you want to do integer arithmetic, like modulo.
2. % is modulo.
3. There is no "f-string" equivalent in Java.

(STARTING CODE)

import java.util.Scanner;

public class Change {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);

/* Type your code here. */
}
}

Answer 1

Hello,

Please find the below code and inline comments:

import java.util.Scanner;

public class Change {
   public static void main(String[] args) {
       int leftover; /* used to hold amount as it decreases */
       int numquarters; /* how many quarters */
       int numdimes; /* how many dimes */
       int numnickels; /* how many nickels */
       int numpennies; /* how many pennies */

       Scanner input = new Scanner(System.in);

       double dollars; // Total value of all the coins, in dollars.

       /* Ask the user for the number of each type of coin. */

       System.out.print("Enter the dollars? :");
       dollars = input.nextDouble();
       int cents = (int) Math.round(100 * dollars);
//       System.out.println(cents);
       leftover = cents;

       numquarters = leftover / 25;
       leftover = leftover % 25;

       /* computer the number of dimes and how much is left over */
       numdimes = leftover / 10;
       leftover = leftover % 10;
       /* computer the number of nickels and how much is left over */
       numnickels = leftover / 5;
       leftover = leftover % 5;
       /* whatever is left over is the number of pennies */
       numpennies = leftover;
       /* print the result */
       System.out.println(numquarters);
       System.out.println(numdimes);
       System.out.println(numnickels);
       System.out.println(numpennies);

   }
}

Project Structure:

Test Result:

Let me know if you have any doubts in the comments sections.

Thanks