__init__.py structure updated.

zerosumset/__init__.py

-
 from z3 import *
 
-elems = [-7, -3, -2, 9000, 5, 8]
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 def zerosumset(elems):
 
-
     n = len(elems)
 
     # Symbolic variables: is_in[i] is 1, if element i is in the zero sum subset, 0 otherwise