From a blank file
to “it works.”

You do not have to write the whole program at once.

Your first goal is small: create one file, run one line, and see one result. Then build each program in pieces you can check.

This workbook accompanies CSC 141 · Programming Assignment 1, covering variables, types, expressions, and formatted output. You can stop after any checkpoint and return later. Your checkmarks are saved in this browser when browser storage is available.

What belongs where?

The handout is the specification. Its due date is September 17, 2026 at 11:59 PM (extended); check D2L for any update. This guide teaches related practice problems. Write and explain your own homework programs, following the assignment’s collaboration and AI rules. The practice files are not submission files.

Open the assignment handout ↗ · Open the course Python Playground ↗

Install the three pieces you need.

VS Code is where you edit files. Python 3 executes the instructions. The Microsoft Python extension connects them. Installing the extension alone does not install Python.

Select the Python interpreter in VS Code

1. Open the Command Palette: Ctrl Shift P on Windows or ⌘ Shift P on macOS.
2. Type Python: Select Interpreter and select that command. Choose your installed Python 3.x. “Interpreter” means the Python program that will run your code.
3. If no interpreter appears, finish installing Python, fully close and reopen VS Code, and try again. If the command itself is missing, check that the Microsoft Python extension is installed and enabled.

Setup references: Python on Windows, Python on macOS, Python in VS Code, VS Code on macOS. Menus can vary slightly by version.

Create → type → save → run.

Create an organized place for your work

1. Open File Explorer (Windows) or Finder (Mac). Inside Documents, create a folder named CSC141_PA1. On Windows, right-click an empty area and choose New → Folder. On Mac, choose File → New Folder.
2. Inside it, create two folders: practice and submission. Practice examples go in practice; your six original homework files go in submission.
3. In VS Code, select File → Open Folder… and choose CSC141_PA1. If asked about workspace trust, trust this folder if it is the folder you just created.
4. Open Explorer in VS Code (the file icon on the left). Right-click the practice folder, select New File, type hello_practice.py, and press Enter. The .py ending tells the editor this is Python.

CSC141_PA1/
    practice/
        hello_practice.py
    submission/
        (your original homework files will go here)

Type these two lines in the editor

print("Hello, CSC 141!")
print(2 + 3)

1. Click the large editor area beside line 1 and type the code above. Use straight quotes ", not curly word-processor quotes. Do not type the line numbers or Markdown backticks.
2. Save with Ctrl S (Windows) or ⌘ S (Mac). If Save As appears, select your practice folder and use the exact name hello_practice.py. The unsaved dot on the tab should disappear.
3. With hello_practice.py as the active tab, select the top-right Run Python File triangle. If needed, use its dropdown or right-click the editor and select Run Python → Run Python File in Terminal. Use the Python extension’s command.
4. Look in the Terminal panel at the bottom. It may first show a long command containing your Python and file paths. Below that command, look for the two lines shown next.

Hello, CSC 141!
5

Now make Python ask you a question

Replace the file’s contents with these two lines, save, and run again:

name = input("Your name: ")
print(f"Hello, {name}!")

When Your name: appears, click inside the terminal, type Jordan without quotes, and press Enter. Python then prints Hello, Jordan!. The waiting cursor is normal: your program is waiting for input.

Understand one line before adding the next.

All practice programs here use straight-line code. You do not need loops, conditionals, classes, or external packages for these exercises. Assume valid inputs as the assignment specifies.

Your reusable “I don’t know how to start” routine

1. Underline the information the user must type. Give each item a descriptive snake_case name and decide whether it is text, int, or float.
2. Write down the required outputs. Next to each one, do a tiny example on paper with easy numbers.
3. Write comment lines beginning with # that describe the steps in English. Put a calculation after the inputs it needs.
4. Implement only the input lines. Save and run. Add a temporary print to check the inputs if useful.
5. Add one calculation. Print its value and compare it to your paper calculation. Repeat for the remaining calculations.
6. Replace temporary checking prints with the required formatted output. Save and test with more than one set of inputs.

Use a header in every homework Python file

# CSC 141 - Programming Assignment 1 - <file name>
# Name: <your full name>
# Date: <the date you finish>
# Description: <one or two sentences describing this program>

Replace the angle-bracket placeholders with your own information. Comments are for people; Python skips them. In these exercises, start normal statements at the left edge. Accidental spaces at the start can cause an unexpected-indentation error.

Practice reasoning before looking at output.

Part A: create a plain-text answer file

Right-click submission → New File → partA.txt. Save your answers as plain text in VS Code. This is a written-answer file, not a Python program, so do not run it with the Python button.

1. For A1, copy each expression from the handout into your answer file. Write your predicted value and type before running anything.
2. Create a separate practice Python file to verify expressions. For a different example, use the code below. A string’s quote marks may disappear when printed, so inspect type() as well.
3. Keep your first prediction. If it was wrong, add the actual result and one sentence explaining the difference.
4. For A2, draw a table with one row per assignment. Update only the variables changed by that line. For a simultaneous swap, read both old right-hand values before updating either name. Then inspect sep and end in each print call to reconstruct spaces and line breaks.
5. For A3, run the handout’s short program in a practice file. Copy the exact last line of the traceback into partA.txt, explain the types involved, and write your fix. A traceback is Python’s description of where execution failed.

sample = 23 // 4
print(sample)
print(type(sample))

For this different example, predict a whole quotient of 5 and type int. Python prints 5 and <class 'int'>.

A1 — expression: [copy from the handout]
My prediction — value: ...   type: ...
Observed — value: ...        type: ...
Explanation if my prediction changed: ...

A2 — trace table and exact printed output:
...

A3 — exact last error line:
...
Why it happens:
...
My correction:
...

Program 1: time_convert.py — a planning checkpoint

This section intentionally provides a plan, not a complete worked solution. Create time_convert.py in submission, add your header, and open the original problem next to it.

1. Identify the input: a whole number of seconds. List the two requested output lines before coding.
2. On paper, draw boxes for complete hours, leftover seconds, complete minutes in that leftover amount, and final seconds. The handout gives the seconds-per-hour conversion.
3. Ask yourself: which operator counts complete groups, and which keeps what did not fit? Use the // and % examples in the toolkit. The number of minutes within the hour differs from the total minutes in the original duration.
4. Write comments describing your sequence, then implement one calculation at a time. Use temporary prints to inspect intermediate quantities.
5. Check the original samples. Also try zero, exactly one minute, and exactly one hour. Do the leftover seconds and within-hour minutes stay between 0 and 59? Format the total-minutes line to two decimal places and remove temporary prints.

Share the cost of a picnic

Program 2 · bill_split.py + Part B

Three friends buy picnic supplies. A delivery fee is a percentage of the supplies cost. Find the fee, the final cost, and the equal share. This practices the same percentage → total → share sequence as the receipt assignment.

# Ask for the supplies cost.
# Ask for the delivery percentage.
# Ask for the number of friends.
# Convert the percentage to a decimal and calculate the fee.
# Add the fee to the supplies cost.
# Divide the total by the number of friends.
# Print a title, aligned costs, the percentage label, and border lines.

supplies_cost = float(input("Supplies cost ($): "))
delivery_percent = float(input("Delivery percent: "))
friends = int(input("Number of friends: "))

delivery_fee = supplies_cost * (delivery_percent / 100)
total_cost = supplies_cost + delivery_fee
cost_per_friend = total_cost / friends

print()
print("PICNIC COSTS")
print("=" * 25)
print(f"{'Supplies:':<17}${supplies_cost:>10.2f}")
fee_label = f"Delivery ({delivery_percent:.1f}%):"
print(f"{fee_label:<17}${delivery_fee:>10.2f}")
print(f"{'Total:':<17}${total_cost:>10.2f}")
print("-" * 25)
print(f"{'Each friend:':<17}${cost_per_friend:>10.2f}")
print("=" * 25)

Run it with these inputs

Type each line below when its prompt appears in the terminal. Press Enter after every input. Do not type quotation marks or slash separators.

48
12.5
3

Expected terminal output

The real terminal shows each value you type next to its prompt. The transcript below includes those typed values.

Supplies cost ($): 48
Delivery percent: 12.5
Number of friends: 3

PICNIC COSTS
=========================
Supplies:        $     48.00
Delivery (12.5%):$      6.00
Total:           $     54.00
-------------------------
Each friend:     $     18.00
=========================

# CSC 141 - PA1 companion practice - practice_picnic.py
# Name: Practice example
# Date: 2026-09-07
# Description: Instructor-provided variant for practice; not a PA1 submission.

# Ask for the supplies cost.
# Ask for the delivery percentage.
# Ask for the number of friends.
# Convert the percentage to a decimal and calculate the fee.
# Add the fee to the supplies cost.
# Divide the total by the number of friends.
# Print a title, aligned costs, the percentage label, and border lines.

supplies_cost = float(input("Supplies cost ($): "))
delivery_percent = float(input("Delivery percent: "))
friends = int(input("Number of friends: "))

delivery_fee = supplies_cost * (delivery_percent / 100)
total_cost = supplies_cost + delivery_fee
cost_per_friend = total_cost / friends

print()
print("PICNIC COSTS")
print("=" * 25)
print(f"{'Supplies:':<17}${supplies_cost:>10.2f}")
fee_label = f"Delivery ({delivery_percent:.1f}%):"
print(f"{fee_label:<17}${delivery_fee:>10.2f}")
print(f"{'Total:':<17}${total_cost:>10.2f}")
print("-" * 25)
print(f"{'Each friend:':<17}${cost_per_friend:>10.2f}")
print("=" * 25)

Test more than the first example

Run the file again for each row. Slashes below separate inputs; type them one at a time, without slashes.

Build a club membership badge

Program 3 · name_tag.py

A club badge shows a member’s full name, whole years since joining, and an approximate number of months. The border must grow when the name grows. This variant uses a joining year, not a birth year.

CURRENT_YEAR = 2026

first_name = input("First name: ")
last_name = input("Last name: ")
join_year = int(input("Year joined: "))

full_name = first_name + " " + last_name
name_length = len(full_name)
years_member = CURRENT_YEAR - join_year
approx_months = years_member * 12

border = "#" * (name_length + 4)
print()
print(border)
print(f"# {full_name} #")
print(border)

print(f"{'Name length:':<17}{name_length} characters")
print(f"{'Years in club:':<17}{years_member}")
print(f"{'Approx. months:':<17}{approx_months}")
print(f"{'Name cheer:':<17}{first_name} {first_name} {first_name}")

Run it with these inputs

Type each line below when its prompt appears in the terminal. Press Enter after every input. Do not type quotation marks or slash separators.

Maya
Chen
2022

Expected terminal output

The real terminal shows each value you type next to its prompt. The transcript below includes those typed values.

First name: Maya
Last name: Chen
Year joined: 2022

#############
# Maya Chen #
#############
Name length:     9 characters
Years in club:   4
Approx. months:  48
Name cheer:      Maya Maya Maya

# CSC 141 - PA1 companion practice - practice_badge.py
# Name: Practice example
# Date: 2026-09-07
# Description: Instructor-provided variant for practice; not a PA1 submission.

CURRENT_YEAR = 2026

first_name = input("First name: ")
last_name = input("Last name: ")
join_year = int(input("Year joined: "))

full_name = first_name + " " + last_name
name_length = len(full_name)
years_member = CURRENT_YEAR - join_year
approx_months = years_member * 12

border = "#" * (name_length + 4)
print()
print(border)
print(f"# {full_name} #")
print(border)

print(f"{'Name length:':<17}{name_length} characters")
print(f"{'Years in club:':<17}{years_member}")
print(f"{'Approx. months:':<17}{approx_months}")
print(f"{'Name cheer:':<17}{first_name} {first_name} {first_name}")

Test more than the first example

Run the file again for each row. Slashes below separate inputs; type them one at a time, without slashes.

Calculate a robot’s motion

Program 4 · free_fall.py

A robot starts from rest and accelerates constantly at 2.5 meters per second squared along a straight track. Given the distance, calculate the travel time and final speed. The arithmetic structure matches the free-fall problem, but the physical situation and constant differ.

ACCELERATION = 2.5
distance = float(input("Track distance in meters: "))

travel_time = (2 * distance / ACCELERATION) ** 0.5

final_speed = ACCELERATION * travel_time
final_speed_kmh = final_speed * 3.6

print(f"Travel time: {travel_time:.2f} s")
print(f"Final speed: {final_speed:.2f} m/s ({final_speed_kmh:.2f} km/h)")

Run it with these inputs

Type each line below when its prompt appears in the terminal. Press Enter after every input. Do not type quotation marks or slash separators.

20

Expected terminal output

The real terminal shows each value you type next to its prompt. The transcript below includes those typed values.

Track distance in meters: 20
Travel time: 4.00 s
Final speed: 10.00 m/s (36.00 km/h)

# CSC 141 - PA1 companion practice - practice_robot.py
# Name: Practice example
# Date: 2026-09-07
# Description: Instructor-provided variant for practice; not a PA1 submission.

ACCELERATION = 2.5
distance = float(input("Track distance in meters: "))

travel_time = (2 * distance / ACCELERATION) ** 0.5

final_speed = ACCELERATION * travel_time
final_speed_kmh = final_speed * 3.6

print(f"Travel time: {travel_time:.2f} s")
print(f"Final speed: {final_speed:.2f} m/s ({final_speed_kmh:.2f} km/h)")

Test more than the first example

Run the file again for each row. Slashes below separate inputs; type them one at a time, without slashes.

Repair a locker-rental calculator

Part D · debug_me.py

A locker rental has a unit price, a quantity, and an 8% service fee. First predict what the broken code does. Then repair one issue at a time. A program can finish without an exception and still produce a completely wrong answer.

First inspect the broken listing

Line numbers below are reference labels; do not type them into your file. Trace with price 7.5 and quantity 4 before opening the repairs.

 1  # Locker rentals with an 8% service fee.
 2  unit_price = input("Locker price ($): ")
 3  quantity = int(input("Number of lockers: "))
 4  subtotal = unit_price * quantity
 5  service_fee = subtotal * 8
 6  total = subtotal + service_fee
 7  print("Total: " + total)

unit_price = float(input("Locker price ($): "))
quantity = int(input("Number of lockers: "))
subtotal = unit_price * quantity

SERVICE_RATE = 0.08
service_fee = subtotal * SERVICE_RATE
total = subtotal + service_fee

print(f"Total: ${total:.2f}")

Run it with these inputs

Type each line below when its prompt appears in the terminal. Press Enter after every input. Do not type quotation marks or slash separators.

7.5
4

Expected terminal output

The real terminal shows each value you type next to its prompt. The transcript below includes those typed values.

Locker price ($): 7.5
Number of lockers: 4
Total: $32.40

# CSC 141 - PA1 companion practice - practice_locker_debug.py
# Name: Practice example
# Date: 2026-09-07
# Description: Instructor-provided variant for practice; not a PA1 submission.

# Bugs in the ORIGINAL numbered locker listing below:
# Line 2: input returned text; convert unit_price with float().
# Line 5: multiplier 8 means 800%; use 0.08 for an 8% fee.
# Line 7: text + numeric total fails after input is fixed; use an f-string.

unit_price = float(input("Locker price ($): "))
quantity = int(input("Number of lockers: "))
subtotal = unit_price * quantity

SERVICE_RATE = 0.08
service_fee = subtotal * SERVICE_RATE
total = subtotal + service_fee

print(f"Total: ${total:.2f}")

Test more than the first example

Run the file again for each row. Slashes below separate inputs; type them one at a time, without slashes.

Use the symptom to choose your next step.

An error message is information about a particular step. Read the last error line first, then the file name and line number above it. Change one thing, save, and run again.

A useful office-hours question

Bring your laptop, the .py file, the input you tried, the expected result, and the actual output or last error line. A specific starting point is enough:

“I can read the three inputs. With these values, I expected the fee to be 6, but it prints repeated text. This is the line I think is involved.”

If you are overwhelmed, pause after one successful checkpoint. You can ask for help before a whole program is finished.

Check the files, then check the ZIP.

Finish your original programs in submission. Keep the practice solutions elsewhere. Part B is included as comments in bill_split.py, so there is no separate Part B file.

submission/
    partA.txt
    time_convert.py
    bill_split.py
    name_tag.py
    free_fall.py
    debug_me.py

1. Save every file. Check that the five Python files have your required header, bill_split.py has your pseudocode, and debug_me.py has your bug list with original line numbers and fixes.
2. Run each .py file separately. Compare against the handout sample, then a second valid case. Remove temporary debugging prints. Open partA.txt and check predictions, types, the trace, and your error explanation.
3. In File Explorer or Finder, open the submission folder. Select exactly the six listed files. On Windows, right-click → Compress to ZIP file (or Send to → Compressed (zipped) folder on older menus). On Mac, right-click → Compress 6 Items.
4. Rename the archive Lastname_Firstname_PA1.zip, using your actual last and first names. Avoid accidentally adding a second .zip extension.
5. Open the ZIP and verify that all six files are present, with the correct extensions. Do not include practice files, screenshots, PDFs, or the guide. If you change a file after making the ZIP, rebuild the ZIP so it contains the updated version.
6. Open D2L → this course → the Programming Assignment 1 submission area. Upload the ZIP and complete the submission action shown there. Check for confirmation and the uploaded filename. D2L controls the current deadline and submission status.

Keep the practice workbook

This page’s lessons, animations, and practice downloads work without a server. External installation links and the course Playground need internet access.

The ZIP contains only practice variants and a README, not homework answers. Printing expands the worked solutions and animation transcripts.