Question

Quick question, I found answers close to this but nothing that helps me. I want it to print out a percentage at the end of the code that has 4 numbers after the decimal point, and of course, using an int work work. But using floats gives me an error.

This code:

import java.util.Scanner;

public class HW2johnson_pp4 {
    public static void main(String args[]) {

        Scanner keyboard = new Scanner(System.in);
        System.out.printf("How many numbers will you enter?\n");
        float[] numbers = new float[keyboard.nextFloat()];

        System.out.printf("Enter " + numbers.length + " integers, one per line:\n");

        for (int i = 0; i <= numbers.length - 1; i++) {
            numbers[i] = keyboard.nextInt();
        }

        float sum = 0;
        for (int i = 0; i <= numbers.length - 1; i++) {
            sum += numbers[i];

        }

        System.out.printf("The sum is " + sum + "\n");

        System.out.printf("The numbers are:\n");

        for (int i = 0; i <= numbers.length - 1; i++) {
            float perc = (numbers[i] / sum);
            float perct = (perc * 100);
            System.out.printf(numbers[i] + " which is " + perct + "%% of the sum.\n");
        }
    }
}

Gives the error:

HW2johnson_pp4.java:8: possible loss of precision
found   : float
required: int
        float[] numbers = new float[keyboard.nextFloat()];

Answer 1

You can’t create an array of floats whose length is a floating-point value. That is to say, you can’t have an array with 2.7 elements.

So the float within the length parameter is getting rounded, causing a loss of precision.

You wanted keyboard.nextInt() there on line 8, and keyboard.nextFloat() below on line 13.