Use admisible graph.
Small stylistic changes.
Flow checker.
Work on price refine.
Added check eps optimality.
Implement push lookahead.
Working heuristics.
Improved update admisible graph.
Added timers.
Added remove_node method.
Updated remove node.
Graph update between iterations.
Time statistics.
Add task nodes back to graph.
Small fixes.
Added check graph valid.
Change graph state.
Moved from pointer to reference.
Small code tidy up.
Refactoring.