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Java

Posted by Benneth Paredis
Benneth Paredis
4,597 Points

please help me with my multiplication program

import java.io.Console;

public class calculator { public static void main(String[] args) { Console console = System.console(); String numberA = console.readLine("type a number: "); String numberB = console.readLine("type a number you want to multiply it with: "); int number1 = Integer.parseInt("numberA"); int number2 = Integer.parseInt("numberB"); int answer = (number1 * number2); //i dont know what to do on this line its so confusing

} }

1 Answer

Derek Markman
Derek Markman
16,291 Points
Derek Markman
Derek Markman
16,291 Points

It's when you're passing in your argument for the parseInt() method. Don't use quotation marks. You would only use quotation marks if you were passing in a string literal like:

import java.io.Console;

public class calculator {
    public static int number1;
    public static int number2;
    public static int answer;
    static Console console = System.console(); 

public static void main(String[] args) { 
//It's also worth noting that doing it this way is redundant, 
//because there is no need to parse to an int, 
//you could just assign number1 and number2 to a '5'.  
//Then print out the answer after you do some sort of operation on the two int variables.

        number1 = Integer.parseInt("5");  //String literal passed in
        number2 = Integer.parseInt("5");  //String literal passed in

        answer = (number1 * number2); 
        System.out.println(answer);
    } 
}

Otherwise you just type the variable directly inside like:

import java.io.Console;

public class calculator {
    public static int number1;
    public static int number2;
    public static String numA;
    public static String numB;
    public static int answer;
    static Console console = System.console(); 

public static void main(String[] args) { 
        numA = console.readLine("type a number: "); 
        numB = console.readLine("type a number you want to multiply it with: "); 

        number1 = Integer.parseInt(numA);  //String variable passed in
        number2 = Integer.parseInt(numB);  //String variable passed in

        answer = (number1 * number2); 
        System.out.println(answer);
    } 
}

Let me know if you have any other questions.