CodeGym/Help with Java Tasks/Help pls --- Error code: 10x10 Table / Array is not *i...

Level 32

San Diego

12.10.2021
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Help pls --- Error code: 10x10 Table / Array is not *initialized / instantiated.

Question about the task

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I have built the Multiplication table 3 different ways. Error code is 10x10 Table / Array is not *initialized / instantiated. No clue ... see code

Initialize the MULTIPLICATION_TABLE array as a new int[10][10], fill it with a multiplication table, and then display it on the console in the following form: 1 2 3 4 … 2 4 6 8 … 3 6 9 12 … 4 8 12 16 … …

The numbers in each line are separated by a space.

Requirements:

In the main method, the MULTIPLICATION_TABLE array must be filled with a multiplication table.
The displayed text should contain 10 lines.
Each displayed line should contain 10 numbers separated by a space.
The displayed numbers must form a multiplication table.

package en.codegym.task.pro.task05.task0509; // import java.io.; /* Multiplication table */ public class Solution { public static int[][] MULTIPLICATION_TABLE; public static void main(String[] args) throws Exception { // public static int[][] MULTIPLICATION_TABLE(int i, int j); // int [][] = new int[i][j]; // int[][] dataBrick = new int[][]; // dataBrick = MULTIPLICATION_TABLE int(); int row = 0; int i = 1; while ( i <= 10 ) { int j = 1; while ( j <= 10 ) { row = row + j; System.out.print(i * j + " "); j++; } System.out.println(""); i++; } } }

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Gellert Varga

Level 23 , Szekesfehervar, Hungary

12 October 2021, 21:57

useful

I would like to highlight what I find very, very important in your writing and what I completely agree with: "There is too much insider Java software jargon in the Forums/Help for newbies. We need more plain speak > simple Step by Step assistance to understand" It is extremely important - essential - in learning anything that the meaning of every single word is very clearly defined. Every teacher should be aware that it is not possible to explain a new thing by throwing in two or three more new unknowns... (which is obvious to her/him, but not to the beginner/questioner...) Unfortunately, in teaching systems this is not always the case. (I'm not just talking about CodeGym.) Therefore, at the moment, the onus is on the learner, if anything starts to get confusing, to immediately go back some steps and find out what the words were that you don't understand or don't understand well enough, and follow up thoroughly. Ask questions on the forum here too. Try to break down what you don't understand into smaller units, and it will be easier to find a clear explanation somewhere on the net. But sometimes you may also need to put aside things you don't fully understand: don't worry, and trust that you'll get a better picture about it later.

Hoist

Level 32 , San Diego, United States

13 October 2021, 04:56

I love the Code Gym platform and all the people whom jump in 24/7 to help. Looking thru the all the different responses and problem solving dialogue is a big learning break-thru approach.

Lisa

Level 41

12 October 2021, 10:31

useful

Yeah.. you were on the right track. The array CG is talking about is declared in line 11. Now you just need to initialize it. Usually that's done that way int[] myArray = new int[SIZE]; Where SIZE should be the length of the array. If the array is already declared (a reference variable has been created), then you just assign the value (the array object) to the reference variable, like:

private static int[] myArray;
myArray = new int[SIZE];

Then you just output a multiplication table... that seems to work but that's not what CG is asking. The ask you to save the multiplication table into the array. Only then, in a new nested loop, you output the contents of the array. Btw., it is probably much easier to use nested for loops for that. To output the array you even could use a for-each loop.

Hoist

Level 32 , San Diego, United States

12 October 2021, 18:56

Thanks Lisa. A very fast response! This helps. Buttt ... it's another bread crumb to follow down a path where by I lack the overall understanding of integrating data objects and control flow. I have looked at 10 examples on Code Gym. I have looked thru 5 examples in stackoverflow. I have a decent basic C# gaming and Javascript background. The total assembly and flow of all the code to solve this -- without enough experience -- is WHY people bail out of Code Gym and quit. The 'moderators' seem too worried that after 3 hours on one Task people might see too much of a solution glued together. I get that. The answers provided by experienced people are too much Java / software speak and way to vague ... the forum members want people to grind more and dig out answers on their own. But they/I/we lack the context to figure it out ! It's just the way of software education... right ?! We are not 'there' yet at level 5/6. So there is delicate balance between brainless copy/paste and trying to fully understand how to handle a complex data object like arrays and also perform functionality together on it to get the desired mutated programmatic results. Again -- I appreciate you jumping in here with a comprehensive response. And many others' do as well. I read boat loads of Help Forum Q&A/ Articles. For me; I usually have to glue to together 2 or 3 responses in different threads to figure stuff out. Most newbies just don't have the tenacity nor bigger Java picture to even understand how to pull it all together at this level .... my 2 cents. Who cares if the moderators or forum members give out too much solution clarity 'help' or code ? Solutions are useless if you don't understand all the different facets to be a successful programmer. There is too much insider Java software jargon in the Forums/Help for newbies. We need more plain speak > simple Step by Step assistance to understand contextually why something flows that way and the syntactical necessity. bravo Code Gym )

Lisa

Level 41

12 October 2021, 19:48

If you want a solution, you could have said that in fewer words 🤪😂🤣 Joking aside, I can really understand what you want to say and I also see it that sometimes after a lesson you just see dozens of question marks. As a complete beginner, even more so. Only codegym is too little there. You still need a beginner's textbook. When a question is asked here in the forum, I usually give tips that I think will be useful. Of course I can't know the level of knowledge of the questioner. He can ask for more information, if that was not enough. And for me, for example, it may not be technical enough. Only if the facts are described as precisely as possible can I understand them. About your questions. Where is the gap? Arrays in general? Already the one-dimensional ones? You have managed the while loop. But a for loop gives you problems? I'll still be online for the next hour. If you are too, maybe I can answer some of your questions. P.S.: hahaha, but be aware.... I'm crazy, yeahahahahahah 😜🤪 (sometimes, no always.... soometiimes)

Guadalupe Gagnon

Level 37 , Tampa, United States

12 October 2021, 19:54

useful

"The total assembly and flow of all the code to solve this -- without enough experience -- is WHY people bail out of Code Gym and quit." I'll have to disagree with you on this. People quit because their learning expectations are far greater than the reality of actually learning. It will take 100's of hours (maybe even 1000's) of reading and practice to become proficient. You don't need to look far online to find articles describing how hard it is to begin learning to program, and it doesn't matter which language or what learning platform you start with. Just type into google "why is programming so hard" and see how many articles through the years were written. Type into google "easy way to learn programming" or "tips to learning programming" and try to find one that makes sense (none of the tips are "revolutionary", typically along the lines of "just do it" and "dont give up"). I don't say this to be disparaging to you or imply that you are not smart enough, I believe programming is a skill that everyone can do with a little bit of help. I hang out a lot in Discord and you can ask me questions there if you need any further explanation/help. Here is the link: discord

Lisa

Level 41

12 October 2021, 20:05

useful

public class Solution {
    public static int[][] MULTIPLICATION_TABLE; // declaration of the array.

    public static void main(String[] args) throws Exception {

        MULTIPLICATION_TABLE = new int[10][10]; // initializing the array - int arrays have default values of 0

        // to loop over an entire two-dimensional array is usually done using a nested for loop
        // the outer loop is iterating over the outer array (the one that holds the inner arrays)
        // the rows so to say.
        for (int i = 0; i < MULTIPLICATION_TABLE.length; i++) {
            // now that we have a row, we can iterate over the cells, the inner array
            for (int j = 0; j < MULTIPLICATION_TABLE[i].length; j++) {
                // the current cell of each iteration you can address using the row address (i) and the cell address (j)
                System.out.print(MULTIPLICATION_TABLE[i][j] + " "); // cause the array is filled with default values it outputs 0
                // if you want to save smth into a cell then use the following syntax
                // MULTIPLICATION_TABLE[i][j] = 5; // to save 5 into the cell...
                // for a muliplication table you probably want to save i* j into it
            }
            System.out.println();
        }
    }
}

Hoist

Level 32 , San Diego, United States

13 October 2021, 04:45

Hi Lisa / Guadalupe )) omg I am glad you are laughing ! lol Thanks for taking the time to write up this walk thru explanation ! It sure helps me -- and I know it will help others' as well. Excellent. I didn't mean to send out a text 'brick' lol I went back on YouTube and only found _one_ good video on wiring up the logic into the data array structure with some detailed explanations about what/why is going on. >> btw .... Guadulape has helped me a bunch on Code Gym since 2018 ! And known for very excellent detailed walk Java walk thru help as well. Totally agree with the commit to 1000's & 1000's of hours required in this software/programming profession ! Well said and very fair response for sure on digging deep into other source materials. Head First Java is my 'go to' with more visuals and YouTube for video lecture. Of course Oracle from vacuuming up Sun Micro .... This is my 2nd time thru Code Gym since 2018 and it is so much more fun and worthwhile. Best

Guadalupe Gagnon

Level 37 , Tampa, United States

13 October 2021, 13:14

Thanks for joining the discord channel. Feel free to ask for help. It is a growing channel of all codegym students of varying degrees of experience. One of them, remote87, started learning programming a year ago and just about 3 weeks ago started his first developer position.

Guadalupe Gagnon

Level 37 , Tampa, United States

13 October 2021, 13:26

Also thanks for not taking anything I said personally. Online, through text chat, it is hard to say "I disagree" without coming off as condescending, which I try really hard not to do. I was a beginner too at one point over my head and know the feeling. I didn't breeze through codegym and struggled quite a bit on some tasks. Back in 2018, when I first started, there was no "download solution" button and the help section had next to no posts in it. It was beyond frustrating failing a task 20+ times and not knowing why. This is why I personally try to add notes on the task pages of confusing tasks, as well as try to answer help questions as clear as possible without using too much "jargon".