[A_Duck]

Trying to do an ELIHN here...

On a holiday of 10 people, everybody exchanging numbers means 10x9/2 = 45 actions, with many of those edges between strangers (higher cost edge)

Each person adding their friend to the Whatsapp group is 9 actions, with all edges between friends (low-cost edge)

So in practice, only the second one happens. He had one other person's number, but that particular person didn't check their phone.

[prmoustache]

What the heck is an ELIHN?

[A_Duck]

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