1. Introduction
As data-processing problems have become more complex, computer scientists have developed data structures to help solve them. A data structure combines several data values into a unit so they can be treated as one thing. The data elements within a data structure are usually organized in a special way that allows the programmer to access and manipulate them. As you saw in previous lectures, a string is a data structure that organizes text as a sequence of characters. In this lecture, we explore the use of common data structures: the list. A list allows the programmer to manipulate a sequence of data values of any types. Lists provide powerful ways to organize data in useful and interesting applications. In addition to exploring the use of lists.
2. Lists
A list is a sequence of data values called items or elements. An item can be of any type. The logical structure of a list is similar to the structure of a string. Each of the items in a list is ordered by position. Like a character in a string, each item in a list has a unique index that specifies its position. The index of the first item is 0, and the index of the last item is the length of the list minus 1. As sequences, lists and strings share many of the same operators but include different sets of methods. We now examine these in detail.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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