Task Cannot Be Passed !!?

Question about the task

Combining arrays

Java Syntax, Level 5, Lesson 1

Resolved

Code not working loll 🤬😭

Implement the main(String[]) method, which needs to copy the contents of the firstArray and secondArray arrays into one resultArray array.
The firstArray array must be at the beginning of the new resultArray array, followed by the secondArray array.

Requirements:

The Solution class must have a public static int[] firstArray variable initialized with an array with 10 values.
The Solution class must have a public static int[] secondArray variable initialized with an array with 10 values.
The Solution class must have a public static int[] resultArray variable.
Implement the main(String[]) method in accordance with the task conditions.

package en.codegym.task.pro.task05.task0504; /* Combining arrays */ public class Solution { public static int[] firstArray = new int[]{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; public static int[] secondArray = new int[]{10, 11, 12, 13, 14, 15, 16, 17, 18, 19}; public static int[] resultArray; public static void main(String[] args) { //write your code here int resultArrayLength = firstArray.length + secondArray.length; resultArray = new int[resultArrayLength]; for (int i = 0; i < firstArray.length; i++) { resultArray[i] = firstArray[i]; } for (int i = 10; i < resultArrayLength; i++) { resultArray[i] = secondArray[i - 10]; } for (int i = 0; i < resultArray.length; i++) { System.out.print(resultArray[i] + ", "); } } }

Comments (6)

Popular
New
Old

You must be signed in to leave a comment

Thomas

Level 41 , Bayreuth, Germany

24 March, 08:42

I suggest to write more universal code. In my experience Codegym often uses several very different test cases to validate your program. If I see the hardcoded 10 inside your loop then I know array access will throw exceptions if I modify the length of the arrays or the result is wrong. You also may want to think about using System.arraycopy() (but I guess that's not the purpose of the task).

PQK

Level 6 , United States of America, Sweden

26 March, 03:12

What do u mean by write universal code ? What are some examples ?

Thomas

Level 41 , Bayreuth, Germany

26 March, 08:04

I don't mean it in a bigger picture (like the SOLID principles - you may want to look it up but it will not tell you much at the moment - later you'll see that this is what you always should keep in mind) but specificially for Codegym. Often when Codegym prepares one testcase for you (like here) then this is just for your convenience but does not mean they test just with that single example. On the contrary they use more different tests than you'd come up with. An example for 'universal code' in your example is when you eg write (like you already did) firstArray.length + secondArray.length Now you could exchange both arrays with other arrays of different length. Still it does not work and gives either wrong results or exceptions. This you need to fix.

PQK

Level 6 , United States of America, Sweden

28 March, 03:59

I still can't find the error tho. Are u able to see if u can correct my code ? Thx.

Thomas

Level 41 , Bayreuth, Germany

28 March, 08:40

I'd try it that way. I have changed the arrays for testing. You may wish to revert that. I also changed the second loop to my way of thinking (just so that you see it can be different ;) ). In your setup you'd need to change 10 to firstArray.length If this still does not validate, hmm.

public class Solution {
    public static int[] firstArray = new int[]{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13};
    public static int[] secondArray = new int[]{14, 15};
    public static int[] resultArray;

    public static void main(String[] args) {
        //write your code here
        resultArray = new int[firstArray.length + secondArray.length];

        for (int i = 0; i < firstArray.length; i++) {
            resultArray[i] = firstArray[i];
        }

        for (int i = 0; i < secondArray.length; i++) {
            resultArray[i + firstArray.length] = secondArray[i];
        }

        // or, instead of the loops, use functionality provided by the Java API
        // System.arraycopy(firstArray, 0, resultArray, 0, firstArray.length);
        // System.arraycopy(secondArray, 0, resultArray, firstArray.length, secondArray.length);

        for (int i = 0; i < resultArray.length; i++) {
            System.out.print(resultArray[i] + ", ");
        }
    }
}

Mattt321 Java Developer

1 April, 08:54

That's my solution as well