The idea

A locker number can be a label or a quantity, depending on your task. Joining "12" and "3" makes "123". Adding 12 and 3 makes 15. input() returns text—even when the reader enters digits. Convert it with int() if you need a whole number. Here the playground supplies input from its Input lines box: put one answer on each line before Run.

A tiny experiment

PYTHON 3PREDICT BEFORE YOU RUN

answer = input("How many clues? ")
clues = int(answer)
print(clues + 1)
print(7 / 2)
print(7 // 2)
print(7 % 2)

Prepared input for this example: 3. The playground supplies it when input() asks.

Run and change this example ↗

Reveal the expected output

How many clues? 4
3.5
3
1

Read it one step at a time

With input 3, int converts the text to an integer and the first calculation produces 4. The prompt appears before that result.
/ gives ordinary division. For these positive numbers, // gives the whole-number quotient.
% gives the remainder: 7 contains three groups of 2, with 1 left over.

Make one change

Keep the input as 3, but change all three 7s to 8. What changes?

Check your thinking

The division results become 4.0 and 4; the remainder becomes 0.

Keep following the trail

Sources & further reading

Python numbers and strings

Companion notes for Coding Adventure by James Colby. Historical claims link to their sources; the examples are written for this learning trail.

Python input, numbers and type conversion