Basic info before starting programming

<Operators>

 

%  gives the remainder of division.

The result of 20%3 is 2.   

It is the most frequently used operator. There is a rule using it.

If you divide 20 by 3, the range of th remainder that you get by % is from 0~2.

 

<Bit and Memory>

 

Computer state is 0 or 1, which is called bit state.

28=256 , which 2 means 0 or 1.

8bit = 1byte

32bit = 4byte

64bit = 8byte

 

<Variable naming convention>

 

- The first letter of the variable must be character, cannot start with numbers and cannot contain special characters. (essential)

ex) int 1num (x) , int speed# (x)

- Exceptional possible special characters : $ , _  (essential)

ex) int _num (o)

- Combination of two words : firstName (conventional)

 

<ASCII code>

 

American Standartd Code Information Interchange code

 

'A'(character type) : 65 (integer type) 

'B' : 66

..............

 

'a' : 97

'b' : 98