# Given blocked_ids = {42, 17, 99, 23} and requests = [12, 17, 5, 99, 42, 7, 23, 100], count how many

Canonical URL: <https://datadriven.io/problems/given-blockedids-42-17-99-23-and-requests-12-17-62344b0b>

Domain: Python · Difficulty: medium

## Problem

Given blocked_ids = {42, 17, 99, 23} and requests = [12, 17, 5, 99, 42, 7, 23, 100], count how many requests target a blocked_id using O(1) set membership. Print the count.

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