`input()` reads data entered by the user. The result of `input()` is initially a string. `int()` converts a numeric string into an integer. The `//` operator performs integer division and keeps the whole-number part. `print()` displays the program result. Print only what the problem statement requires.

**Connection to this task.** The `//` operator performs floor integer division. It is useful for counting how many complete groups of a fixed size fit into a value. The expression `n // 100` shows how this idea is applied to the task data.

For this task, pay special attention to `int(input())`: it connects the concept above to the concrete computation or program action.

**Focus: “First Digit of a Four-Digit Number”.** The same basic mechanism is used in a different context here, so understand the operation itself rather than memorizing a finished line of code.