How can i add a input to the "valor2" ? - java

Question

I just started to learn java, someone knows, how can i ask like "Type your values", and add id to the double[] valor2 ?

class test { // body start
    public static void main(String [] args) {
      
        double[] valor2 = {15, 4864, 4, 21}; // here is my doubt
     
        for (int a=0; a<valor2.length; a++){
            System.out.format("%s %d: O valor deste item é %10.2f %s%n", "Item", a+1, valor2[a], "reais");
        }
    }
}

Answer 1

Use a Scanner for inputs.

public class TypeYours {

    public static void main(String[] args) {
        // Double array to contain the values
        double[] values = new double[4];

        // The scanner take System.in (console input stream) as input.
        Scanner scanner = new Scanner(System.in); /
        
        for (int a = 0; a < values.length; a++) {
            System.out.print("Enter a price:");

            // Store the scanned value
            values[a] = scanner.nextDouble();

            // Some %s is unnecessary so I removed them. 
            // Also, not %n but \n to start a new Line
            System.out.format("Item %d: O valor deste item é %10.2f reais\n", a + 1, values[a]);
        }
    }

}

Note that this is a very simple example: 1) The size of the double[] is hardcoded in the source as 4. If you want to dynamically change the values's size, use ArrayList<Double> or some other instead. 2) Scanner can take int, float, String as well, try them in your coed. 3) System.out.format can be replaced by the combination of System.out.print() and String.format(format, ...args), which is more flexible.