Distinct customer ids

Problem

A shop lists the customer id on every order of the day. Count how many different customers placed orders.

Ids are compared as text, so A1 and a1 are different customers.

Example

Input

101 102 101 103 102

Output

Three different ids: 101, 102 and 103.

Try the problem first. Open one hint at a time.

Hint 1

A set keeps one copy of each value.

Hint 2

Split the line into a list, make a set from it and print its length.

Write your Python code, run it on the examples and submit it to hidden tests.