Abstract: Because the software requirement specification focuses on the user requirements,it is not easy to describe and modify the internal logic of the complex algorithm.The flow chart is inclined to the bottom of the program design,it is convenient for the implementation of automatic program design,but lacks of high-level semantics,and has no mechanism to modify,update and backup,the logic complexity of modification is still very large,the cost of flow chart design and maintenance is also very high,and it is still not convenient to describe the uncertain program logic.To solve the practical problems in the designing and maintaining complex algorithms,this paper proposes a light-weight method to describe the internal logic of complex algorithm based on thinking map,which adapts to the characteristics of uncertain internal workflow and long-term R&D process.This paper formally defines the logical model of thinking map firstly,then discusses the object-oriented implementation of thinking map,as well as the program simulation for the inheritance and polymorphic scene of the objective world.And it takes the semantic recognition of text data element variables as an example,specifically describes the stage and process of designing and maintaining complex algorithms by thinking map.Finally,it summarizes the whole paper and puts forward some suggestions,the next research task of thinking map is also proposed

Key words: Complex algorithm, Data element, Semantic recognition, Software engineering, Thinking map