# Given ids = [101, 102, 103, 104, 105], write an O(1) lookup that prints ids[0] and ids[len(ids) - 1]

Canonical URL: <https://datadriven.io/problems/given-ids-101-102-103-104-105-write-an-o1-lookup-2481bbc4>

Domain: Python · Difficulty: medium

## Problem

Given ids = [101, 102, 103, 104, 105], write an O(1) lookup that prints ids[0] and ids[len(ids) - 1] (the first and last).

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