Essential JavaScript

Looping Over Numbers

We have already seen an example of how to loop through numbers one-by-one.

We can loop over any range of numbers, starting at any number, moving up or down by any increment.

We could start at 5, move up in increments of 5, and stop once we get to 30 or above:

let i = 5;
while (i < 30) {
  i += 5;

We could start at -3, move down in increments of -6, and stop once we get to -21 or below:

let i = -3;
while (i >= -21) {
  i -= 6;

Loops give us the flexibility to handle any repeating work with numbers.

Learning Goals

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