My Learning Notes – Python Basics (Day Learning Blog)

Today’s class was focused on basic Python concepts and some logical problems. Even though the topics are simple, they form the foundation for programming. I am writing this blog to revise what I learned in my own words.

sep and end in Python

In Python, the print() function has default behavior:

• It adds space between multiple values
• It moves to the next line after printing

We can control this using sep and end.

• sep (separator): used to define what comes between values
• end: used to define what comes at the end of the output

Example:

print("hi", "hello", sep=" ", end="*")
print(5)

Output:

hi hello*5

This means:

• sep=" " keeps space between words
• end="*" prevents new line and adds * instead

This concept is useful when formatting output.

Functions in Python

A function is a reusable block of code designed to perform a specific task.

Instead of writing the same logic again and again, we use functions. This improves code readability and reduces duplication.

A function can take input values called arguments and can return output.

Arguments in Functions

Arguments are values passed to a function when it is called.

Types of arguments (basic idea):

• Required arguments
• Default arguments
• Variable-length arguments

Arguments make functions flexible and reusable.

Polymorphism

Polymorphism means “many forms”.

In programming, it means:

• A single function or operation behaves differently based on input

Example:

• Adding two numbers → numeric addition
• Adding two strings → string concatenation

So, same operation but different behavior.

Method Overloading

Method overloading means:

• Same function name
• Different number or type of arguments

Python does not support traditional method overloading like some languages, but we can achieve similar behavior using default arguments or conditions.

Sum of First n Natural Numbers

We learned a mathematical formula:

n(n + 1) / 2

This formula gives the sum of first n numbers.

Example:
For n = 10
Sum = 10 × 11 / 2 = 55

Using loop:

bag = 0 
day = 1
while day <= 10:
    bag = bag + day
    day = day + 1
print(bag)

This loop keeps adding numbers one by one.

Identity Elements in Mathematics

Two important concepts:

• Additive Identity:
  Adding 0 does not change the value
  Example: 5 + 0 = 5

• Multiplicative Identity:
  Multiplying by 1 does not change the value
  Example: 5 × 1 = 5

These are basic but important in logic building.

Multiplication of First n Numbers

This is similar to sum, but instead of addition we use multiplication.

total = 1
no = 1
while no <= 5:
    total = total * no
    no = no + 1
print(total)

Factorial Concept

Factorial of a number means multiplying all numbers from 1 to that number.

Example:
5! = 5 × 4 × 3 × 2 × 1

Code:

factorial = 1
no = 1
while no <= 5:
    factorial = factorial * no
    no = no + 1
print(factorial)

Reverse approach:

factorial = 1
no = 5
while no >= 1:
    factorial = factorial * no
    no = no - 1
print(factorial)

Both methods give the same result.

Logic Problem – Frog Climbing

This problem is about simulation using loops.

Given:

• Frog starts at 50 feet
• Climbs 2 feet every time
• Slips down 1.25 feet

We need to find how many steps or days it takes.

feet = 50
up = 2
down = 1.25
day = 0

while feet > 0:
    feet = feet - up + down
    day = day + 1

print(day)

This type of problem improves logical thinking and loop understanding.