Lesson 8: for Loops and range()

Topics Covered:

• Understanding for loops
• Using the range() function
• Looping through lists and strings

What is a for Loop?

A for loop repeats a block of code a specific number of times or over a sequence.

for i in range(5):
    print("Hello!")

Using range()

range() generates numbers:

for i in range(1, 6):
    print(i)

range(start, stop) starts at the first number and ends just before the second number.

Counting with Steps

for i in range(0, 10, 2):
    print(i)  # Prints even numbers from 0 to 8

Looping Through a List

animals = ["cat", "dog", "bird"]

for animal in animals:
    print("I like", animal)

Looping Through a String

word = "Python"

for letter in word:
    print(letter)

Activity: Print Numbers

Print all numbers from 1 to 10 and say if they are even or odd:

for num in range(1, 11):
    if num % 2 == 0:
        print(num, "is even")
    else:
        print(num, "is odd")

Challenge

• Ask the user for a number.
• Print a multiplication table up to 10 for that number.

num = int(input("Enter a number: "))

for i in range(1, 11):
    print(num, "x", i, "=", num * i)