K2-MDD-based maximum common sub-graph matching method with labeled graph

The invention discloses a k2-MDD-based maximum common sub-graph matching method with a labeled graph. The method comprises the steps of screening vertex labels of a matching graph, selecting vertexessame as a target graph labeled in the matching graph, and changing labels of the vertexes into labels of the vertexes corresponding to the vertexes in the target graph to obtain a new matching graph;encoding the vertexes of the target graph and the new matching graph according to the rule of the k2 tree; encoding the edges of the target graph and the new matching graph according to the vertex codes of the target graph and the new matching graph; constructing a multi-valued decision graph structure according to the codes of the edges of the target graph and the new matching graph to obtain k2-MDD structure graphs of the target graph and the new matching graph; and in the constructed k2-MDD structure graphs of the target graph and the matching graph, solving the maximum common sub-graph ofthe target graph and the ma