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Java

Posted by Björn Norén
Björn Norén
9,569 Points

Print a returned array

Hello there! I want to turn an int array of elements to zeros, but I don't know how to print a returned array. I get something like: I@sdgodfnos;

Is there anyone who knows how to print a returned array? I want it to look something like this: [0, 0, 0, 0, 0]

Thanks! 

public static int[] createIntArray(int l)
    {
        int[] array = new int[l];
        for (int i=0; i<l; i++)
        {
            array[i] = 0;       
        }
        return array;
    }

    public static void main (String[] args)
    {   
    Integer[] C = {1, 2, 3, 4, 5};

    System.out.println(createIntArray(C.length));

    }

2 Answers

Steve Goldman
Steve Goldman
2,345 Points

When you ask Java to print an array it just prints out the memory address of the array. That is those weird mumbo-jumbo letters/numbers.

We have to tell Java to actually go through that memory address and print what's inside it. You can either make a for loop to go through the array and print out each index or you can use Java's Arrays.toString(insert your array here) method.

Hope that helps.

Björn Norén
Björn Norén
9,569 Points

Yes, it helped. :) Thanks for taking your time to explain!

Kourosh Raeen
Kourosh Raeen
23,733 Points
Kourosh Raeen
Kourosh Raeen
23,733 Points

println will not produce the output you want but you can write a function that does that. You can use a string declared and initialized outside a for loop:

String output = "[";

Then in the for loop keep concatenating the array elements to output and also adding the comma. Once you're done with the loop concatenate "]" and return the string.

Björn Norén
Björn Norén
9,569 Points

Ah, I see! So the new function should be a void? Thanks!

Kourosh Raeen
Kourosh Raeen
23,733 Points

The way I described it above it wouldn't be void. It would return a string like [0, 0, 0, 0, 0] so to print it you just pass the return value of that function to println(), but you could make it a void function and do the printing inside the function. I personally prefer for the function to only return the string and do the printing elsewhere.