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💛 — Calculator: + − × ÷

Task​

  • Create a file named calculator.py.
  • Read two numbers (use float) from input.
  • Print the results of: +, -, *, /.
  • If the second number is 0, don’t crash on division (print a message).
  • (Optional) Ask for the operator (+ - * /) and only do that one.
  • (Optional) Round results to 2 decimals.

Example run​

$ python calculator.py
a: 10
b: 4
a + b = 14.0
a - b = 6.0
a * b = 40.0
a / b = 2.5

Solution (ATTEMPT FIRST)​

Show spoiler code (calculator.py)

This prints all four operations, with a safe divide-by-zero check. An optional single-op mode is included in comments.

calculator.py
"""calculator.py

A tiny calculator. We'll be polite about division by zero.
"""

def read_number(prompt: str) -> float:
    """Read a float from input, retrying until valid."""
    while True:
        s = input(prompt).strip()
        try:
            return float(s)
        except ValueError:
            print("Please enter a number like 3 or 2.5")

a = read_number("a: ")
b = read_number("b: ")

print(f"a + b = {a + b}")
print(f"a - b = {a - b}")
print(f"a * b = {a * b}")

if b == 0:
    print("a / b = (nope) division by zero is illegal in this kingdom")
else:
    print(f"a / b = {a / b}")

# --- Optional single-operator mode (commented) ---
# op = input("Choose op (+ - * /): ").strip()
# if op == "+": print(a + b)
# elif op == "-": print(a - b)
# elif op == "*": print(a * b)
# elif op == "/":
#     print("nope" if b == 0 else a / b)
# else:
#     print("Unknown operator")

Docs / Tutorials​