Hi there,

I am trying to solve this problem : http://codeforces.com/contest/302/problem/C, however even on reading the editorial I am not able to get how to solve it.

Editorial link.

Editorial says that it can be solved using dfs but I am not even able to figure out the graph in the problem.

Further, most of solutions I have read are doing this :

if((n is odd) || (n is even and #negatives is even)) ans= sum of absolute values of all numbers

else ans=sum of absolute values of all numbers-2*(abs(element with minimum absolute value)) ``

Can you please help me in understanding how this is working and how to apply dfs in this ?

Thanks in advance.