A Common-Sense Guide to Data Structures and Algorithms in JavaScript, Volume 1

Measuring Speed

So how do we measure the speed of an operation?

If you take away just one thing from this book, let it be this: when we measure how “fast” an operation is, we do not refer to how fast the operation takes in terms of pure time but instead in how many steps it takes.

We’ve actually seen this earlier in the context of printing the even numbers from 2 to 100. The second version of that function was faster because it took half as many steps as the first version did.

Why do we measure code’s speed in terms of steps?

We do this because we can never say definitively that any operation takes, say, five seconds. While a piece of code may take five seconds on a particular computer, that same piece of code may take longer on an older piece ...