ERROR: This method must return a result of type int

Question

Code:

import java.util.*;

public class shuffleDeck
{ 
    public static int shuffleDeck (int[] deck, int theNumber)
    {
        int [] array1         


        

Answer 1

Based on your main method, I suppose, that what you want is to shuffle the deck for the given count of times, for that you should update the method as follows:

public static void shuffleDeck (int[] deck, int theNumber)
{
    Random random = new Random();
    for (int k=0; k < theNumber; k++) {
        for (int i = deck.length, j, tmp; i > 1; i--) {
            j = random.nextInt(i);

            tmp = deck[i - 1];
            deck[i - 1] = deck[j];
            deck[j] = tmp;
        }
    }
}

for returning the number of how many times you actually did the shuffle doesn't make sense ... based on your input. The inner loop, as posted in https://stackoverflow.com/a/30757452/4234940 is only the shuffle itself... so actually I would change it like this:

public static void shuffleDeck (int[] deck, int theNumber)
{
    Random random = new Random();
    for (int k=0; k < theNumber; k++) {
        shuffle(deck, random);
    }
}

private static void shuffle(int[] array, Random random){
    for (int i = array.length, j, tmp; i > 1; i--) {
        j = random.nextInt(i);

        tmp = array[i - 1];
        array[i - 1] = array[j];
        array[j] = tmp;
    }
}