# Given nums = [1, 2, 2, 3, 3, 3, 4, 4, 4, 4], use a dict to count occurrences in a single pass (O(n))

Canonical URL: <https://datadriven.io/problems/given-nums-1-2-2-3-3-3-4-4-4-4-use-a-dict-to-c-41c423fc>

Domain: Python · Difficulty: medium

## Problem

Given nums = [1, 2, 2, 3, 3, 3, 4, 4, 4, 4], use a dict to count occurrences in a single pass (O(n)). Print the dict sorted by key.

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