How to solve problem Odd Cycle from ACM-ICPC Asia — Daejeon regional contest.
The statement briefly:
Given simple directed graph having no self-loops or multiple edges, detect if it has any directed odd cycle (cycle with odd length) and if yes print description of an arbitrary odd cycle of the input graph.
The graph has n nodes
( n <= 100000 ) , m edges
( m <= 1000000).