Bit Arrays

In order to proceed, we need to talk quickly about bit arrays. Bit arrays are exactly how they sound, they are just an array of bits. They are useful for indicating whether something is included in a set or not.

Let's explore how bitwise operations affect numbers, quickly.

For example, a bit wise AND will only allow the bits that both values share in their respective places.

0b110 & 0b011 = 0b010

Bitwise OR will have a bit switched on every place that is switched on either value.

0b110 | 0b011 = 0b111

A bit wise, exclusive OR will leave a bit on only if exactly one of the bits are on in both values.

0b110 ^ 0b011 = 0b101

We use bit arrays to indicate whether or not an outcome is part of a specific set of outcomes.

One very efficient way to represent bit arrays is with unsigned integers, like so.

0b001 == 1
0b010 == 2
0b011 == 3
0b100 == 4
0b101 == 5
0b111 == 6

Now that we have an idea of what bit arrays are, we can talk about index sets and outcome collections.

← ConditionsBasic Outcome Collections →