11 Programing concepts
Chapter Overview
- Basic data types
- Integer
- Real number
- Char
- String
- Boolean
- Programming
- Rules in naming variable
- Sequence
- Selection
- Iteration
- Totalling
- Counting
Note: All codes in this article are written in Python
11.1 Basic data types
INTEGER
A positive or negative whole number that can be used with mathematical operators.
REAL
A number with a fractional part, that can be used with mathematical operators.
Not all programming languages distinguish between real numbers and integers. For example, JavaScript makes no distinction but Python does.
Integer = int(25) // Declare an integer with the value of 25
Real = float(25) // Declare a real number with the value of 25.0
CHAR
A single character.
Char = 'A'
Char = "A"
STRING
A string variable has several characters in length. String vary in length and may even have no characters. The characters can be lettersand/or digits and/or any other printable symbols. For example:
exam_name = 'CIE'
subject_code = '0478'
entry_password = '@!&*%^$#'
BOOLEAN
A boolean variable can have only two values: TRUE or FALSE
pass_CIE_exam_with_help_of_SCIEprogrammer = TRUE
11.2 Programming
RULES IN NAMING VARIABLES
- Case-sensitive (number1 is different from Number1)
- Can contain numbers, letters and underscore
- CAN NOT start with a number
- CAN NOT be the same as Python Reserved words
E.g. max, min, sum - USE DESCRIPTIVE NAMES and ADD COMMENTS
Otherwise, you’ll lose mark in CIE EXAM !
SEQUENCE
Statements that runs one by one in order.
first_num = int(input('Enter the first whole number:'))
second_num = int(input('Enter the second whole number:'))
total = first_num + second_num
print('The sum equals', total)
SELECTION
Running the following statements depends on whether the criteria given is satisfied or not. In Python we use IF statement:
if grade == 100:
print('Excellent! You got TOP IN THE WORLD in computer science.')
elif grade > 80:
print('Great! You can improve by spending more effort.')
else:
print('Oops! You need more hard work.')
Difference between single equal sign (=) and double equal signs (==)
- Single Equal Sign means to assign value or content or variable on right to the variable on the left
- It means ‘