Statements are something like so: Given n and an array of n integers 1 ≤ ai ≤ n, 
Needed answer "NO" if this is not possible to divide the array into two groups of same sum or answer "YES" and print all numbers in first group and second group.
The task sounds similar to knapsack problem, and I know only the greedy approach this problem, but I know that this should be possible (according to problem editorial) to solve it with 
with knapsack approach.
Link to Editorial (Russian only) and to problem Statements (Also russian only)
I hope you will be able to help me. :]
