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range

Learn number sequences with range().

The range function

range generates a number range. range(5) generates 0 through 4:

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

range(2, 6) gives 2 through 5. range(0, 10, 2) gives 0 to 9 in steps of 2 (0, 2, 4, 6, 8). range is not a list but a range object; to convert use list(range(5)).

The range step parameter

range can take three parameters: range(start, stop, step):

for i in range(0, 10, 2):
    print(i)  # 0 2 4 6 8

for i in range(10, 0, -1):
    print(i)  # 10 9 8 ... 1

A negative step counts backwards. This is handy for countdowns and skipping loops.

Practice Print with range

Write for i in range(3): print(i).

Starter code

main.py
# Loop with range

Sample solution

main.py
for i in range(3):
    print(i)

Expected output

0
1
2

Questions and answers

Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.

1 What numbers does range(3) produce?

  • 1, 2, 3
  • 0, 1, 2 Correct answer
  • 0, 1, 2, 3
  • 3

Explanation: range(3) produces 0, 1, 2.

2 Complete range

Question 
for i in ____(5):
    print(i)
Answer 
for i in range(5):
    print(i)

Explanation: Number ranges use range.

3 Match the range forms

Term Meaning
range(5) 0-4
range(2, 6) 2-5
range(0, 10, 2) 0,2,4,6,8
range(10, 0, -1) 10 down to 1

All lessons in Beginner

1 Python basics

  1. What is Python?
  2. REPL and print
  3. Comments
  4. Indentation blocks
  5. python -c and scripts
  6. Summary - Python basics

2 Variables

  1. Variable assignment
  2. Multiple assignment
  3. Naming variables
  4. id and type
  5. Swapping variables
  6. Summary - Variables

3 Data types

  1. int and float
  2. bool
  3. str basics
  4. None
  5. Type conversion
  6. Summary - Data types

4 Project: Calculator

  1. Project design
  2. Add/subtract
  3. Multiply/divide
  4. Error handling
  5. Putting it together

5 Operators

  1. Arithmetic
  2. Comparison
  3. Logical
  4. Bitwise
  5. Membership and identity
  6. Summary - Operators

6 String basics

  1. f-string
  2. Concatenation
  3. str.format
  4. Raw strings
  5. Triple-quote
  6. Summary - String basics

7 Conditionals

  1. The if statement
  2. elif and else
  3. Nested if
  4. Truthiness
  5. Conditional expression
  6. Summary - Conditionals

8 Loops

  1. The for loop
  2. range
  3. The while loop
  4. break and continue
  5. Loop else
  6. Summary - Loops

9 Project: Shopping cart

  1. Cart design
  2. Adding items
  3. Calculating totals
  4. Updating quantity
  5. Putting it together

10 Lists

  1. Declaring lists
  2. Index and slice
  3. List methods
  4. in and count
  5. Sorting lists
  6. Summary - Lists

11 List comprehension

  1. Comprehension basics
  2. Filtered comprehension
  3. Dict and set comprehension
  4. Nested comprehension
  5. Generator expression
  6. Summary - List comprehension

12 Tuple, set and dict

  1. Tuple
  2. Set
  3. Dict basics
  4. Dict methods
  5. Dict comprehension
  6. Summary - Tuple, set and dict

13 Functions

  1. def
  2. return
  3. Docstring
  4. Default parameters
  5. *args and **kwargs
  6. Summary - Functions

14 Function parameters

  1. Positional parameters
  2. Keyword parameters
  3. Keyword-only
  4. Positional-only
  5. Type hints basics
  6. Summary - Function parameters

15 Project: To-do CLI

  1. Task model
  2. Adding tasks
  3. Listing tasks
  4. Completing tasks
  5. Putting it together

16 Advanced string methods

  1. split and join
  2. strip, lstrip, rstrip
  3. replace
  4. find and index
  5. startswith, endswith
  6. Summary - Advanced strings

17 Input and output

  1. input()
  2. int/float conversion
  3. print parameters
  4. f-string formatting
  5. sys.argv
  6. Summary - Input and output

18 Error handling

  1. try/except
  2. else and finally
  3. raise
  4. Exception hierarchy
  5. Custom exceptions
  6. Summary - Error handling

19 Modules

  1. import
  2. from import
  3. as alias
  4. __name__ == '__main__'
  5. Standard library
  6. Summary - Modules

20 Beginner final

  1. Project design
  2. Data model
  3. Business logic
  4. Error handling
  5. Putting it together