Learn With Frahim

Day 7: Functions, Loops, and Conditional Statements

Step 1: Functions

Functions allow you to encapsulate code for reuse.

# Defining a function

def greet(name):

  print(f"Hello, {name}!")

# Calling a function

greet("Alisha")

Explanation: Functions take input arguments, perform actions, and can optionally return a value using return.

Function with Return Value

def square(num):

  return num * num

result = square(5)

print(result)  # Output: 25

Step 2: Conditional Statements

Use if, elif, and else to control program flow.

age = 18

if age >= 18:

  print("You are an adult")

elif age >= 13:

  print("You are a teenager")

else:

  print("You are a child")

Explanation: Conditions are evaluated in order. The first True condition executes its block.

Step 3: For Loops

For loops iterate over a sequence (list, tuple, string, range).

# Loop over a list

fruits = ["Apple", "Banana", "Cherry"]

for fruit in fruits:

  print(fruit)

# Loop with range

for i in range(1, 6):  # 1 to 5

  print(i)

Step 4: While Loops

While loops execute as long as the condition is True.

count = 1

while count <= 5:

  print(count)

  count += 1

Step 5: Combining Loops and Conditionals

Example: Print only even numbers from a list.

numbers = [1, 2, 3, 4, 5, 6]

for num in numbers:

  if num % 2 == 0:

    print(num)

Step 6: PyCharm Project Layout

        FunctionsLoopsProject

        ├── functions_demo.py

        ├── if_demo.py

        ├── for_loop_demo.py

        └── while_loop_demo.py

# Example: functions_demo.py
def square(num):

  return num * num

print(square(7))

Step 7: Tips & Best Practices

Use functions to avoid repeating code and improve readability.
Use meaningful variable names inside loops and functions.
Be careful with loop conditions to avoid infinite loops.
Use break and continue wisely in loops.
Indentation is crucial in Python for loops and conditionals.

✔ End of Day 7 – You now understand Functions, Conditional Statements, Loops, and can structure projects in PyCharm efficiently!

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