Tell us what’s happening:
Hi,
I understand where the error in the challenge code is (maybe I don’t understand it completely), but I can’t figure out why zeroArray(3, 2) returns:
[[0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0]]I would expect:
[ [ 0, 0], [0, 0, 0, 0], [0, 0, 0, 0, 0, 0] ]row is equal to [0, 0] , then [0, 0, 0, 0] and then [0, 0, 0, 0, 0, 0].Let’s consider the end of the inner loop first iteration:
row is now [0, 0], and it gets pushed into newArray. Even if row is global and its value doesn’t get initialized at every inner loop, why at the end of the function newArray[0] == [0, 0, 0, 0, 0, 0] and not [0, 0] ? I don’t get it.Thank you
Your code so far
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
for (let j = 0; j < n; j++) {
// Pushes n zeroes into the current row to create the columns
row.push(0);
}
// Pushes the current row, which now has n zeroes in it, to the array
newArray.push(row);
}
return newArray;
}
let matrix = zeroArray(3, 2);
console.log(matrix);
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Challenge: Use Caution When Reinitializing Variables Inside a Loop
Link to the challenge:
