--- each_strongly_connected_component_from(node) {|nodes| ...}
#    iterates over strongly connected component in the subgraph reachable from 
#    node.

    node ãǽʶϢʬˤĤƤΥƥ졼Ǥ

#    Return value is unspecified.
    ֤ͤϵꤵƤޤ

#    each_strongly_connected_component_from doesn't call
#    tsort_each_node.
    each_strongly_connected_component_from 
    tsort_each_node ƤӤޤ

