The Social Graph

A easy Python interview practice problem on DataDriven. Write and execute real python code with instant grading.

Domain

Python

Difficulty

easy

Seniority

L3

Problem

Given a list of groups (each group is a list of person names), compute per-person friend count: for a group [A, B], both A and B gain each other as friends. For a singleton [X], X exists but gains no friend from that row. Friendships are deduplicated: if A and B appear together in multiple groups, it is still one friendship. Return a dict mapping each person to their distinct friend count.

Summary

Everyone knows someone.

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