Could you please explain the logic behind Step 111 (Building a Pyramid Generator)?

JavaScript
1

The .push() method makes sense but the .unshift() method makes me confuse. Could you please help me how .unshift() method makes the pyramid inverted?

Thank you!

2

can you share the code you are asking about? the unshift method adds stuff at the beginning of the array, without the context in which it is used it’s impossible to say its relation to the pyramid

5

please post the code not a screenshot

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6

Gotcha, thank you! Here:

const character = "#";
const count = 8;
const rows = [];

function padRow(rowNumber, rowCount) {
  return " ".repeat(rowCount - rowNumber) + character.repeat(2 * rowNumber - 1) + " ".repeat(rowCount - rowNumber);
}

for (let i = 1; i <= count; i++) {
  rows.push(padRow(i, count));
}

let result = ""

for (const row of rows) {
  result = result + row + "\n";
}

console.log(result);

That gives me a pyramid and when you replace .push() with .unshift(), the pyramid becomes inverted:

for (let i = 1; i <= count; i++) {
  rows.unshift(padRow(i, count));
}
7

you have the first line.
push add the second line after the first line, the pyramid grows larger going down.
unshift add the second line before the first line, the pyramid grows larger going up

8

Thank you! I also used the visual simulator and I got it finally. Really thank you!

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