1. A method of sensitizing a sequential circuit, said sensitizing generating stimuli to drive any circuit output to a predetermined value or transition, the method comprising: creating a directed graph of the sequential circuit, the directed graph comprising a plurality of nodes, including primary nodes associated with primary inputs of the sequential circuit, one or more internal nodes and an output node associated with an output of the sequential circuit; topologically sorting the plurality of nodes of the directed graph to generate sorted nodes, wherein said topologically sorting includes determining longest data flow distances from the primary nodes to each of the one or more internal nodes and the output node; and using a computer, generating final vectors for the sequential circuit based on the longest data flow distances of the sorted nodes, the final vectors expressed only by primary inputs to the sequential circuit.