🧮 7-Day Calculator Quest

Before You Start

Write down whatever you mess up on in a notebook and write down the solution that worked. If you weren't able to finish, write down a guess.

🌱 Day 1: Basic Setup

Goal: Ask for two numbers and an operator (+, -, *, /).

1. Use input() three times to collect:
   • First number
   • Operator
   • Second number
2. Convert the numbers from strings to a number.
3. Print all three inputs (e.g., 5 + 3.0). Don't solve yet, just print it.

Extension: What if you want to write 0.5 + 0.5? Which type is right to cast to?

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🔥 Day 1.5: Operation Logic

Goal: Perform calculations based on the operator.

1. Check the operator and do the operation. Hint: use multiple ifs.
2. You can't divide by 0, ask google why if you don't understand it. Handle division by zero (print "Error: Can't divide by 0!").

Hint:

• Add ** (exponent) and % (modulo) as new operators.
• Don't understand what they mean? Before Googling, just add the if statements for these operations and try plugging in random numbers.

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🛡️ Day 2: Input Validation

Goal: Ensure inputs are valid.

1. Check if the numbers are actually numbers (Hint: Google how)
2. Print an error if the operator isn't valid.
3. If invalid, print "Invalid input!" and stop.
4. Test operator=4 and other weird code. What does it do?

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♾️ Day 3: Looping & Exiting

Goal: Let the user keep calculating until they say "quit".

1. Wrap the calculator in a while True: loop. Find out what this does.
2. Ask after each calculation: "Continue? (yes/no)".
3. Exit the loop if they type "no".

Hint:

• Google break statement.

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🔥 Extra Challenge: Day 4: History Tracking

Goal: Save the last 5 calculations using variables.

This problem is challenging! Highly suggest you draw the flow of the code on paper first.

1. Create 5 variables:

   hist1 = ""  
   hist2 = ""  
   hist3 = ""  
   hist4 = ""  
   hist5 = ""  

2. After each calculation, update the history:
   • Shift old entries (e.g., hist5 = hist4, hist4 = hist3, ...)
   • Save the newest to hist1: "5.0 + 3.0 = 8.0"
3. Print all 5 entries after each calculation.

Debug Challenge:

• What happens if you do hist5 = hist4 after updating hist1?