Maxtrix from debugging lessons

I can’t figure out why different locating make different outcomes

debugging lessons

Please post your code instead of a picture of your code so that we can best help. A link to the challenge you are working on would also be helpful.

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Hi, I believe you are referring to this challenge:

The row initialization before the nested for loop causes row to never reset, and since newArray.push(row) is pushing by reference, every row in newArray becomes [0,0,0,0,0,0].

Reinitializing row every time it loops in the outer for loop allows you to have a fresh row to mutate without mutating the rows already pushed into newArray, and you can have the correct number of 0s pushed into row every loop, instead of row getting longer and longer with each outer for loop.

You can see the difference by using console.log

function zeroArray(m, n) {
  // Creates a 2-D array with m rows and n columns of zeroes
  let newArray = [];
  let row=[];
  for (let i = 0; i < m; i++) {
    // Adds the m-th row into newArray
    row = [];
    for (let j = 0; j < n; j++) {
      // Pushes n zeroes into the current row to create the columns
    // Pushes the current row, which now has n zeroes in it, to the array
  return newArray;

let matrix = zeroArray(3, 2);

You can ask for help on specific challenges by clicking Get HelpAsk For Help below Run The Tests in the challenge. This way FCC automatically links the correct challenge.

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Thanks u for suggestion Sir
I’ll follow your instruction next time

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