2 problems i'v encountered doing some job, not as easy as it may seems...

1. you are given a set of some integer numbers (some is probebly around 60-70). As integers some of the numbers are negative and some positive. You need to find maximal sub-set which the sum of it's elements it's 0 ( zero +- 1).
for ex: {-1,1,1,1,1,3,-2,-7} will have the answer of {1,1,1,1,3,-7}.

2.you got a DAG (directed acyclic graph) already topolpgical sorted. you want to find the minimum number of distinct paths that will cover all vertices of the graph. for ex: if you got a->b->c->d->e then you got one path that will cover the graph.