Name: Anonymous 2014-07-02 13:05
A set of integers is sum-free when addition always gets you out of the set (i.e. x + y = z has no solutions -- in other words S + S and S are disjoint). Formally, let S be a subset of N. S is sum-free if for all a,b in S, a+b is not in S.
Now, let S be any set of nonzero integers. Find a subset of size > |S|/3.
You may use your favoritelisp language.
I've got a really nice solution for this one.
Now, let S be any set of nonzero integers. Find a subset of size > |S|/3.
You may use your favorite
I've got a really nice solution for this one.