What are abstract data types

Abstract data type refers to a mathematical model and a set of operations defined on the model. It only depends on its logical characteristics and has nothing to do with how the computer is represented and implemented internally. It embodies the decomposition of problems in programming. and information hiding characteristics.

Abstract data type (ADT) refers toa mathematical model and a set of data defined on the model operate. It only depends on its logical characteristics and has nothing to do with how it is represented and implemented inside the computer. For example, the integer type just mentioned. Every computer, whether mainframe, minicomputer, PC, tablet or even smartphone, has an "integer" type, which also requires integer operations. So the integer type is actually an abstract data type. .

According to the definition of an abstract data type, it also includes a set of

operations on that model. Just like the classic Nintendo game "Super Mario", the protagonist of the game is Mario. We have defined basic operations for him, such as forward, backward, jumping, shooting bullets, etc. This is an abstract data type that defines a data object, the relationship between elements in the object, and operations on the data elements.

As for what operations they are, this can only be determined by the designer based on actual needs. For example, Mario may only be able to walk and jump at first, but later he found that he should add an operation to shoot bullets, and then he added the operation of pressing and holding the bullet button and moving forward to run. This is all determined based on the actual situation.

#In fact, abstract data types embody the characteristics of problem decomposition and information hiding in programming. It decomposes the problem into multiple smaller and easier-to-handle problems, and then implements each functional module as an independent unit, and realizes the entire problem through one or more calls.

Supplement:

Representation and format of abstract data types:

ADT = （D,S,P） （D：数据对象 S：D上的关系集 P：D上的一组操作）

ADT 抽象数据类型名称{
      数据对象：<数据对象的定义>；
      数据关系：<数据关系的定义>；
      基本操作：<基本操作的定义>
}

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