references/C/1_variables.md

Variables

Declare then use variables

(optional initialiser) e.g. int hens = 5

Variables should be declared seperately.

If variables aren't initialised it'll try to get some value from the stack, causing massive unprodictibiliy. Always initialse.

Types

These types store a certain amount of data, in bits.

• int

• float

• double

• char

• unsigned

• short

• long

Signed and Unsigned

integers are signed by default, allowing negatives and positives.

Unsigned ints, etc. have all their bits for positive values.

Local Variables

These are only usable and accessible withing the scope of the current function

Static Varialbles

Static variables retain their value within the function, regardless of how many function calls.

static int hens;

Static variables default their initialisation to 0. And are not re-initialised upon function calls. These variables retain their value until the program is restarted, etc.

Sharing static varialbes

By declaring the static variable within the source code, not inside of a function it can be used by many functions.

Global?