UNIT 3 – PROGRAMMING FUNDAMENTALS 3.8 Operators CLASS XI COMPUTER SCIENCE – FBISE

Описание: WHAT IS AN OPERATOR

An operator is a symbol or keyword that tells the computer to perform a specific operation on one or more values called operands. Operators are used to perform calculations, compare values, test conditions, and manipulate data in a program.

Example
result = 10 plus 5

Here, plus is the operator and 10 and 5 are operands.

TYPES OF OPERATORS IN PYTHON (FBISE SYLLABUS)

According to the syllabus, the following operators are included:

Arithmetic operators

Bitwise operators

Membership operators

Comparison operators

Each type of operator has a specific role in programming.

3.8.1 ARITHMETIC OPERATORS

Arithmetic operators are used to perform mathematical calculations.

LIST OF ARITHMETIC OPERATORS

Addition
Symbol: plus
Example: 5 plus 3
Result: 8

Subtraction
Symbol: minus
Example: 5 minus 3
Result: 2

Multiplication
Symbol: star
Example: 5 multiplied by 3
Result: 15

Division
Symbol: slash
Example: 5 divided by 2
Result: 2.5

Modulus
Symbol: percent
Example: 5 modulus 2
Result: 1

Floor Division
Symbol: double slash
Example: 5 floor divided by 2
Result: 2

Exponentiation
Symbol: double star
Example: 2 power 3
Result: 8

ARITHMETIC OPERATOR EXAMPLES IN PYTHON

a = 10
b = 3

print(a + b)
print(a - b)
print(a * b)
print(a / b)
print(a % b)
print(a // b)
print(a ** b)

IMPORTANT NOTES FOR EXAMS

Division always produces a decimal result
Floor division removes the decimal part
Modulus gives remainder
Exponentiation is used for power calculations

3.8.2 BITWISE OPERATORS

Bitwise operators work on the binary form of numbers. These operators perform operations directly on bits, which makes them important for low-level programming.

Example
Decimal 5 in binary is 101
Decimal 3 in binary is 011

LIST OF BITWISE OPERATORS

Bitwise AND
Symbol: ampersand
Works when both bits are one

Bitwise OR
Symbol: vertical bar
Works when at least one bit is one

Bitwise XOR
Symbol: caret
Works when bits are different

Bitwise NOT
Symbol: tilde
Inverts all bits

Left Shift
Symbol: double left shift
Moves bits to the left

Right Shift
Symbol: double right shift
Moves bits to the right

BITWISE AND EXAMPLE

5 AND 3

Binary calculation
101
011
Result: 001 which is 1

BITWISE OR EXAMPLE

5 OR 3

Binary calculation
101
011
Result: 111 which is 7

BITWISE XOR EXAMPLE

5 XOR 3

Binary calculation
101
011
Result: 110 which is 6

BITWISE NOT EXAMPLE

NOT 5

Result is minus 6

Explanation
Bitwise NOT uses two’s complement logic
Formula: NOT x equals negative of x plus one

LEFT SHIFT OPERATOR

Example
5 left shift 1

Binary
101 becomes 1010

Result is 10

Each left shift multiplies the number by 2

RIGHT SHIFT OPERATOR

Example
5 right shift 1

Binary
101 becomes 10

Result is 2

Each right shift divides the number by 2

IMPORTANT FBISE NOTES

Bitwise operators work only with integers
Left shift fills zeros on the right
Right shift removes rightmost bits
Used in system-level and optimization tasks

3.8.3 MEMBERSHIP OPERATORS

Membership operators are used to check whether a value exists in a sequence such as a string or a list.

MEMBERSHIP OPERATORS

in
Returns true if value exists

not in
Returns true if value does not exist

EXAMPLE WITH STRING

text = "Pakistan"

print("P" in text)
print("x" in text)

EXAMPLE WITH LIST

numbers = [1, 2, 3, 4]

print(3 in numbers)
print(10 not in numbers)

USAGE IN CONDITIONS

if "a" in "apple":
print("Found")

Membership operators are commonly used in decision-making logic.

3.8.4 COMPARISON OPERATORS

Comparison operators are used to compare two values. The result of a comparison is always true or false.

LIST OF COMPARISON OPERATORS (WRITTEN FORM)

Equal to
Not equal to
Greater than
Less than
Greater than or equal to
Less than or equal to

COMPARISON EXAMPLES IN PYTHON

a = 10
b = 20

print(a equals b)
print(a not equals b)
print(a greater than b)
print(a less than b)
print(a greater than or equal to b)
print(a less than or equal to b)

STRING COMPARISON EXAMPLE

print("apple" equals "apple")
print("Apple" equals "apple")

Python comparisons are case-sensitive.

USE IN DECISION MAKING

marks = 75

if marks greater than or equal to 50:
print("Pass")
else:
print("Fail")

IMPORTANT EXAM POINTS

Comparison operators return Boolean values
Used with if and while statements
Assignment is different from comparison
Confusing assignment with comparison is a common mistake

CONCLUSION

Operators are the foundation of programming logic. Arithmetic operators perform calculations, bitwise operators work on binary data, membership operators test presence in sequences, and comparison operators help in decision making. A strong understanding of operators is essential for solving problems and writing efficient Python programs.