(Day 05) Task : Python Loops & Password Generator Task :-

Loops in Python :-

For Loop :-

• A for loop is used to repeat a block of code for each item in a sequence (like a list, string, or range of numbers).

Syntax of a for loop :-

for item in sequence:
    # do something with item

• item: A variable name you choose (like fruit, number, etc.)

• sequence: A list, string, range, etc.

• The code inside the loop runs once for each item in the sequence.

Why use a for loop?

• When you want to do something multiple times, especially for every item in a group.

• Example:

  • Print every fruit in a basket, one by one.

  •   fruits = ["apple", "peach", "banana"]
      for fruit in fruits:
          # Process each fruit here
          print(fruit)
    

  • Here it’s assigning the values of fruits to a variable fruit.

for loops and the range() Function:-

• When you use for loops with the range() function, you're telling Python:

  “Hey, repeat this code a certain number of times.”

What does range() do?

• The range() function generates a sequence of numbers.

•   range(start, stop, step)
  

• start: The number to begin from (default is 0).

• stop: The number to stop before.

• step: How much to increment each time (default is 1).

range() can be defined in three parts :-

1. Use for i in range(n) to repeat code n times :-

• Do something n times. It's a simple way to repeat a block of code again and again.

• range(n) creates a list of numbers from 0 to n-1

• Note :- Remember range() excludes the stop number.

  • Example :-

    •   for i in range(5):
            print(i)             # Output : 0, 1, 2, 3, 4
      

    • This prints numbers: 0, 1, 2, 3, 4

    • Starts from 0 by default, ends before 5 (as it excludes the stop number).

2. Use range(start, stop) to control where it begins and ends :-

• “Start counting from start and stop before stop".

  You're telling Python exactly where to begin and where to end the loop.

• start → the number where the loop starts

• stop → the number where the loop ends (but not included) ❌

• The loop runs from start to stop - 1.

  • Example :-

    • Print roll numbers from 1 to 30:

    •   for roll_no in range(1, 31):
            print(f"Roll Number: {roll_no}")
      

3. Use range(start, stop, step) for custom steps :-

   “Start from start, stop before stop, and jump by step each time.”

   You're not just telling Python where to start and stop, but also how big each jump (step) should be.

• start → where the loop begins.

• stop → where it stops (but not included).

• step → how much to increase or decrease each time.

  • Example :-

    •   for i in range(2, 11, 2):
            print(i)            # Output :- 2 4 6 8 10
      

• Note :-

  • You can use positive steps (count up).

  • Or negative steps (count down).

  • If step is not given, it defaults to 1.

Project :- You are going to write a program that automatically prints the solution to the FizzBuzz game. These are the rules of the FizzBuzz game: Your program should print each number from 1 to 100 in turn and include number 100. But when the number is divisible by 3 then instead of printing the number it should print "Fizz". When the number is divisible by 5, then instead of printing the number it should print "Buzz". And if the number is divisible by both 3 and 5 e.g. 15 then instead of the number it should print "FizzBuzz"

# FizzBuzz from 1 to 100

for number in range(1, 101):  # Includes 100
    if number % 3 == 0 and number % 5 == 0:
        print("FizzBuzz")  # Divisible by both 3 and 5
    elif number % 3 == 0:
        print("Fizz")      # Divisible by 3 only
    elif number % 5 == 0:
        print("Buzz")      # Divisible by 5 only
    else:
        print(number)      # Not divisible by 3 or 5

Password Generator :-