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← Challenges easy

count the edges from degrees

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A graph on 5 vertices has degree sequence: \deg(v3)=1, \deg(v5)=1, \deg(v2)=1, \deg(v4)=1, \deg(v1)=4.

Predict the number of edges |E|, using the handshaking theorem -- no drawing is given.

Close enough! points.

Not quite.

You predicted — the actual value was .

+ XP

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