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学び始める
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Abstraction means separating the top level usefulness of a thing from the details of its implementation so that the programmers is freed from worrying about details.
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what are the 2 modern methods for abstraction 学び始める
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control/process abstraction and data abstraction
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explain control/process abstraction 学び始める
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Process abstraction is necessary for achieving program modularity, which means dividing up a system into components or modules, each of which can be designed, implemented, tested, reasoned about, and reused separately from the rest of the system.
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学び始める
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Data abstraction enforces a clear separation between the abstract properties of a data type and the concrete details of its implementation.
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what does an ADT consist of 学び始める
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a set of data, and necessary operations on the data.
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what are Abstract Data Types (ADTs) 学び始める
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An abstract data type is a user-defined data type
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学び始める
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For example, List is a widely used data structure Data: a collection of items, each item has a position in a sequential order. Operations: add/remove an item, sort the items,...
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what must be decieded when designing an ADT 学び始める
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a set of core operations for users to use the data type. The core operations support the basic uses of the data
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what are the basic rules for ADT design 学び始める
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[1] Basic information should not be difficult to obtain [2] The set of operations should be adequate [3] Each operation should have a well-defined purpose [4] Have a few simple operations that can be combined to perform more complex operations.
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what do you need when Implementing an ADT 学び始める
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To implement an ADT, you need to choose: a data representation and algorithms.
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what is ADT data representation 学び始める
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[1] internal storage container is used to hold the items in the collection, e. g an array [2] users of the ADT need not know the representation [3] users not allowed to tamper with the representation [4] all data private [5] use accessors and mutators
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学び始める
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[1] An algorithm for each of the necessary operations, e.g., an algorithm for sorting a list. [2] All auxiliary (helper) operations that are not in the contract should be private.
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