III Командный Студенческий Чемпионат Урала, Екатеринбург, Март 19 - 20, 1999
Find a multiple
Given n positive integers, each is not greater than 15000. This numbers are not necessarily different (so it may happen that two or more of them will be equal). Your task is to choose a few of given numbers (1 ≤ few ≤ n) so that the sum of chosen numbers is multiple for n (i.e. n * k = (sum of chosen numbers) for some integer k).
First line contains number n (n ≤ 10000). Each of next n lines contains one number from the given set.
If the answer can not be found, print 0. Otherwise print the number of the chosen numbers in the first line followed by the chosen numbers themselves (on a separate line each) in arbitrary order.
If there are more than one set of numbers with required properties, print any of them.
5 1 2 3 4 1
2 2 3