Protip: Compute the size before you allocate

I've lost track of how many times I've seen code that uses a dynamically-expanding array when it could've easily calculated the correct size and allocated exactly the right amount. See: string appending, tokenising, just about everything written in JavaScript, etc.

No wonder software is so slow and bloated...

>>19
each time you run out of space double the array in size.

Since it grows 1, 2, 4, 8, 16, 32, 64, ... you very very quickly reach a state where it's big enough and doesn't need to resize.