There are 1001 student at a certain school. Prove that at least one of them must have an even number of friends among the other 1000 students. (You should assume that friendship is symmetric so that if A is a friend of B, then B is a friend of A.)(adsbygoogle = window.adsbygoogle || []).push({});

Can anyone help me on this problem? Thanks

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# Homework Help: Student at School

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