2023年全國碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
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1、<p><b>  附件A</b></p><p><b>  編程語言</b></p><p>  編寫計(jì)算機(jī)程序有兩種常用方法:面向過程的程序設(shè)計(jì)和面向?qū)ο蟮某绦蛟O(shè)計(jì)。</p><p>  面向?qū)ο蟮某绦蛟O(shè)計(jì)是面向過程程序設(shè)計(jì)的一種擴(kuò)展,在編寫程序時采用的方法有一些不同,用面向?qū)ο蟮姆椒紤]問題,首先把程序元

2、素看成是與現(xiàn)實(shí)世界中的具體對象相似的對象,然后對這些對象進(jìn)行操作以得到期望的結(jié)果。編寫面向?qū)ο蟮某绦虬▌?chuàng)建對象和創(chuàng)建使用這些對象的應(yīng)用程序。</p><p><b>  機(jī)器語言</b></p><p>  能被計(jì)算機(jī)操作系統(tǒng)直接運(yùn)行的計(jì)算機(jī)程序稱為可執(zhí)行程序。可執(zhí)行程序是以機(jī)器碼的形勢表示的一系列非常簡單的指令。這些指令對于不同計(jì)算機(jī)的CPU而言是特定的,它們與硬

3、件有關(guān)。例如,英特爾“奔騰”處理器和Power PC微處理器芯片各自有不同的機(jī)器語言,要求用不同的代碼集來完成相同的任務(wù)。機(jī)器碼指令是從存儲單元取數(shù)據(jù),或?qū)蓚€存儲單元的內(nèi)容相加(通常在CPU的寄存器中進(jìn)行)。機(jī)器碼指令是二進(jìn)制的——比特序列(0和1)。由于這些數(shù)字令人難以理解,所以計(jì)算機(jī)指令通常不是用機(jī)器碼來寫的。</p><p><b>  匯編語言</b></p><

4、;p>  與機(jī)器語言指令相比,匯編語言使用的命令較容易為程序員理解。每條機(jī)器語言指令在匯編語言中有等價(jià)的命令。例如,在匯編語言中,語句“MOV A,B”命令表示計(jì)算機(jī)把數(shù)據(jù)從一個單元復(fù)制到另一個單元,而及其代碼中同樣的指令是有一串16位的0和1組成的。一旦匯編語言程序編寫完畢,它就由另一個稱之為匯編起的程序轉(zhuǎn)換成機(jī)器語言程序。相對于機(jī)器語言而言,匯編語言速度快,功能強(qiáng)??伤匀浑y以利用,因?yàn)閰R編語言指令是有一系列抽象代碼組成的。另

5、外,不同的CPU使用不同的機(jī)器語言,因此需要不同的匯編語言(程序)。有時為了執(zhí)行特殊的硬件任務(wù),或者為了加快高級語言程序的速度,匯編語言被插入到高級語言程序中。</p><p><b>  高級語言</b></p><p>  從機(jī)器語言進(jìn)步到匯編語言,是語言達(dá)到了更先進(jìn)的階段。同樣也正是這種進(jìn)步導(dǎo)致了高級語言的發(fā)展。如果計(jì)算機(jī)能把簡便的符號翻譯成基本操作,為什么它就

6、不能完成其他文字類型的編碼功能呢?</p><p>  現(xiàn)在讓我們來看看所期望的高級語言應(yīng)有的特點(diǎn),以及怎樣將它們與機(jī)器碼和匯編語言進(jìn)行比較。高級程序語言是這樣一種編程手段,它用規(guī)范化的術(shù)語來寫出一步步的程序步驟,執(zhí)行這些步驟時會用唯一確定的方式處理工作。高級語言經(jīng)常針對某類特殊的處理問題而設(shè)計(jì),例如,一些語言設(shè)計(jì)成適宜處理科學(xué)計(jì)算問題,另一些語言則更側(cè)重于文件處理的應(yīng)用。</p><p>

7、;<b>  面向?qū)ο缶幊陶Z言</b></p><p>  像C++這樣的面向?qū)ο蟪绦蛘Z言(OOP)是以傳統(tǒng)的高級語言為基礎(chǔ),但是它們能使程序員按照組合對象集方式而不是指令列表方式來進(jìn)行思考。對象有許多性質(zhì),以圓為例,就有圓的半徑以及把圓畫到計(jì)算機(jī)屏幕上的命令。對象的類可以從其他對象類那里繼承屬性。例如,一個定義正方形的類能從定義長方形的類那里繼承諸如直角這樣的屬性。程序類的這種關(guān)系簡化了程

8、序員的工作,從而導(dǎo)致更多既可靠又高效的程序產(chǎn)生。</p><p><b>  附件B</b></p><p>  Programming Language</p><p>  There are two popular approaches to writing computer programs: procedural programming

9、(面向過程的程序設(shè)計(jì)) and object-oriented programming(面向?qū)ο蟮某绦蛟O(shè)計(jì)).</p><p>  Machine Language</p><p>  Computer programs that can be run by a computer’s operating system are called executables(可執(zhí)行程序). An ex

10、ecutable program is a sequence(序列) of(一系列的) extremely(非常地) simple instructions known as machine code. These instructions are specific to the individual computer’s CPU and associated(相關(guān)的) hardware; for example, Intel Pent

11、ium and Power PC microprocessor chips each have different machine languages and require different sets of codes to perform the same task. Machine code instructions are few in nu</p><p>  Assembly Language匯編語

12、言</p><p>  Assembly language uses commands that are easier for programmers to understand than machine-language commands. Each machine language instruction has an equivalent(等價(jià)的) command in assembly language.

13、 For example, in assembly language, the statement “MOV A,B”instructs(命令) the computer to copy data from one location to another. The same instruction in machine code is a string of (一串)16 0s and 1s. Once an assembly-lang

14、uage program is written, it is converted to a machine-language program by another pr</p><p>  High-Level Languages</p><p>  The improvement of machine language to assembly language set the stage

15、 for further advances. It was this improvement that led, in turn, to the development of high-level languages. If the computer could translate convenient symbols into basic operations, why couldn’t it also perform other c

16、lerical coding functions?</p><p>  Let us now look at the features we would expect to find in a high-level language and how they compare with machine code and assembly language.[3] A high-level programming l

17、anguage is a means of data in a uniquely defined way. It may bear no relation to any given computer but does assume that a computer is going to be used. The high-level languagees are often oriented toward a particular cl

18、ass of processing problems. For example, a number of languages have been designed to process problems of a s</p><p>  Object-Oriented Programming Languages</p><p>  Object-oriented programming(O

19、OP)languages like C++ are based on traditional high-level languages, but they enable a programmer to think in terms of collections of cooperating objects instead of lists of commands. Objects, such as a circle, have prop

20、erties such as the radius of the circle and the command that draws it on the computer screen.[4] Classes of objects can inherit features such as right angles from a class edfining rectangles. This set of programming clas

21、ses simplifies the progammer’s </p><p>  The long-term productivity of systems is enhanced by object-oriented program. Because of the modular nature of the code, programs are more malleable. This is particul

22、arly beneficial for applications that will be used for many years, during which company needs may change and make software modifications necessary. Software reliability can be improved by object-oriented programming. Sin

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