# Find all values that appear more than once in the list

Canonical URL: <https://datadriven.io/problems/find-all-values-that-appear-more-than-once-in-the-list-use-5fa459b7>

Domain: Python · Difficulty: medium

## Problem

Find all values that appear more than once in the list. Use a 'seen' set and a 'duplicates' set: for each value, if it is already in seen add it to duplicates, otherwise add it to seen. Print the duplicates as a sorted list.

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