Datatypes in C Programming

<div dir="ltr" style="text-align: left;" trbidi="on"> <table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody> <tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjYq-bSCZjnIWCR4v4TyK17NsbELxIEbGJLdFoQWLq2c8EvenxKku3K6lsgoxQiv9fNJV0_eb3e20W-l5Y8OmT4trLm3tWeivED3L6AvGek0W3ldRbCn_4h2S4k5GfqnDxFMOo_DWyWFgI/s1600/Data+Types+in+C.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="470" data-original-width="627" height="476" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjYq-bSCZjnIWCR4v4TyK17NsbELxIEbGJLdFoQWLq2c8EvenxKku3K6lsgoxQiv9fNJV0_eb3e20W-l5Y8OmT4trLm3tWeivED3L6AvGek0W3ldRbCn_4h2S4k5GfqnDxFMOo_DWyWFgI/s640/Data+Types+in+C.jpg" width="640" /></a></td></tr> <tr><td class="tr-caption" style="text-align: center;"><h2> <b><span style="color: red;"><u>Datatypes in C Programming</u></span></b></h2> </td></tr> </tbody></table> <div class="separator" style="clear: both; text-align: left;"> <b>Datatypes</b> in C Program DATA TYPES  C supports several different types of data, each of which may be represented differently within the computer’s memory. The basic data types are listed below. Typical memory requirements are also given. (The memory requirements for each data type will determine the permissible range of values for that data type. Note that the memory requirements for each data type may vary from one C compiler to another.)  int integer quantity 2 bytes or one word (varies from one compiler to another) char single character 1 byte float floating-point number (i.e., a number containing 1 word (4 bytes) a decimal point andor an exponent) double double-precision floating-point number (i.e., more 2 words (8 bytes) significant figures, and an exponent which may be larger in magnitude)  C compilers written for personal computers or small minicomputers (i.e., computers whose natural word size is less than 32 bits) generally represent a word as 4 bytes (32 bits). The basic data types can be augmented by the use of the data type qualijiers short, long, signed and unsigned. For example, integer quantities can be defined as short int, long int or unsigned int (these data types are usually written simply as short, long or unsigned, and are understood to be integers). The interpretation of a qualified integer data type will vary from one C compiler to another, though there are some commonsense relationships. Thus, a short int may require less memory than an ordinary int or it may require the same amount of memory as an ordinary int, but it will never exceed an ordinary int in word length. Similarly, a long int may require the same amount of memory as an ordinary int or it may require more memory, but it will never be less than an ordinary int . If short int and int both have the same memory requirements (e.g., 2 bytes), then long int will generally have double the requirements (e.g., 4 bytes). Or if int and long int both have the same memory requiremements (e.g., 4 bytes) then short int will generally have half the memory requirements (e.g., 2 bytes). Remember that the specifics will vary from one C compiler to another. An unsigned int has the same memory requirements as an ordinary int. However, in the case of an ordinary int (or a short int or a long int), the leftmost bit is reserved for the sign. With an unsigned int, all of the bits are used to represent the numerical value. Thus, an unsigned int can be approximately twice as large as an ordinary int (though, of course, negative values are not permitted). For example, if an ordinary int can vary from -32,768 to +32,767 (which is typical for a 2-byte int), then an unsigned int will be allowed to vary from 0 to 65,535. The unsigned qualifier can also be applied to other qualified ints, e.g., unsigned short int or unsigned long int. The char type is used to represent individual characters. Hence, the char type will generally require only one byte of memory. Each char type has an equivalent integer interpretation, however, so that a char is a really a special kind of short integer (see Sec. 2.4). With most compilers, a char data type will permit a range of values extending from 0 to 255. Some compilers represent the char data type as having a range of values extending from -128 to +127. There may also be unsigned char data (with typical values ranging from 0 to 255), or signed char data (with values ranging from -128 to +127). Some compilers permit the qualifier long to be applied to float or to double, e.g., long float, or long double. However, the meaning of these data types will vary from one C compiler to another. Thus, long float may be equivalent to double. Moreover, long double may be equivalent to double, or it may refer to a separate, “extra-large” double-precision data type requiring more than two words of memory. </div> <div class="separator" style="clear: both; text-align: left;"> <br /></div> <div class="separator" style="clear: both; text-align: left;"> <b><span style="color: red;"><a href="https://www.youtube.com/channel/UCfl-GMB6Coqg9MEWp-e1UDw?sub_confirmation=1" target="_blank">👉See videos more up to date........</a></span></b></div> <div class="separator" style="clear: both; text-align: left;"> <b><br /></b></div> <div class="separator" style="clear: both;"> <b>CONSTANTS </b></div> <div class="separator" style="clear: both;"> There are four basic types of constants in C. They are integer constants,floating-pointconstants, character constants and string constants (there are also enumeration constants, which are discussed in Sec. 14.1). Moreover, there are several different kinds of integer and floating-point constants, as discussed below. Integer and floating-point constants represent numbers. They are often referred to collectively as numeric-type constants. The following rules apply to all numeric-type constants. 1. Commas and blank spaces cannot be included within the constant. 2. The constant can be preceded by a minus (-) sign if desired. (Actually the minus sign is an operator that changes the sign of a positive constant, though it can be thought of as a part of the constant itself.) 3. The value of a constant cannot exceed specified minimum and maximum bounds. For each type of constant, these bounds will vary from one C compiler to another. Let us consider each type of constant individually. </div> <div class="separator" style="clear: both;"> Integer Constants </div> <div class="separator" style="clear: both;"> An integer constant is an integer-valued number. Thus it consists of a sequence of digits. Integer constants can be written in three different number systems: decimal (base lO), octal (base 8) and hexadecimal (base 16). Beginning programmers rarely, however, use anything other than decimal integer constants. A decimal integer constant can consist of any combination of digits taken from the set 0 through 9. If the constant contains two or more digits, the first digit must be something other than 0. </div> <div class="separator" style="clear: both;"> EXAMPLE 2.4 Several valid decimal integer constants are shown below. </div> <div class="separator" style="clear: both;"> 0 1 743 5280 32767 9999 </div> <div class="separator" style="clear: both;"> <br /></div> <div class="separator" style="clear: both;"> The following decimal integer constants are written incorrectly for the reasons stated. </div> <div class="separator" style="clear: both;"> 12,245 illegal character (, ). 36.0 illegal character (.). 10 20 30 illegal character (blank space). 123-45-6789 illegal character (-). 0900 the first digit cannot be a zero. </div> <div class="separator" style="clear: both;"> An octal integer constant can consist of any combination of digits taken from the set 0 through 7. However the first digit must be 0,in order to identiQ the constant as an octal number. </div> <div class="separator" style="clear: both;"> EXAMPLE 2.5 Several valid octal integer constants are shown below. </div> <div class="separator" style="clear: both;"> 0 01 0743 077777 </div> <div class="separator" style="clear: both;"> <br /></div> <div class="separator" style="clear: both;"> The following octal integer constants are written incorrectly for the reasons stated. </div> <div class="separator" style="clear: both;"> </div> <div class="separator" style="clear: both;"> 743 Does not begin with 0. 05280 Illegal digit (8). 0777.777 Illegal character ( .). </div> <div class="separator" style="clear: both; text-align: left;"> <b><br /></b></div> <div class="separator" style="clear: both; text-align: left;"> <b><br /></b></div> </div>

Datatypes in C Programming Datatypes in C Program DATA TYPES  C supports several different types of data, each of which may be repr...

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c vs c++

<div dir="ltr" style="text-align: left;" trbidi="on"> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgeWk9fKTEv7vVZSA8TO856dEh23EDLJtmsu_4bxQQI5LHayiEekIbB_scQsEMxxiDxRMe3y_ZjoIwSnzStHWaeT2H5cwkX288hPVu5tMBxXLhOoZgFGOU2T1-BOICRUfeIMHbuULCSfhw/s1600/maxresdefault.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="720" data-original-width="1280" height="360" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgeWk9fKTEv7vVZSA8TO856dEh23EDLJtmsu_4bxQQI5LHayiEekIbB_scQsEMxxiDxRMe3y_ZjoIwSnzStHWaeT2H5cwkX288hPVu5tMBxXLhOoZgFGOU2T1-BOICRUfeIMHbuULCSfhw/s640/maxresdefault.jpg" width="640" /></a></div> <h2 style="text-align: center;"> <b><u>c vs c++</u></b></h2> <div> <div> <br /></div> <div> Before concluding this chapter, a few words about C++ are in order. Newcomers are sometimes confused about what C++ is and how it differs from C. In short, C++ is an object-oriented programming language that was built upon the foundation of C. In general terms, C is a subset of C++, or conversely, C++ is a superset of C.</div> <div> In general, you can use a C++ compiler to compile a C program. In fact, today most compilers handle both C and C++ programs. Thus, most programmers will use a C++ compiler to compile their C code! However, since C++ was built upon the 1989 C standard, you must restrict your C code to the features defined by that standard (which are the features described in Part One of this book).</div> <div> There is one thing that you must be careful about when using a C++ compiler to compile a C program: the file extension. By convention, C programs use the .C extension. C++ programs use .CPP. Don't accidentally give your C program a .CPP extension. Differences between the two languages might prevent a valid C program from being compiled as if it were a C++ program. By specifying the .C extension, you are telling the C++ compiler to perform a ''C compile."</div> <div> <br /></div> <div> <div> NOTE:- </div> <div> For a complete description of the C++ language, see C++: The Complete Reference, by Herbert Schildt (Berkeley, CA: Osborne/McGraw-Hill).</div> </div> <div style="font-weight: bold;"> <br /></div> </div> </div>

c vs c++ Before concluding this chapter, a few words about C++ are in order. Newcomers are sometimes confused about what C++ is and...

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Compilers vs. Interpreter in C programming

<div dir="ltr" style="text-align: left;" trbidi="on"> <h2 style="text-align: center;"> <b><span style="color: blue;">Compilers vs. Interpreters</span></b></h2> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhhJy0K3zbi4465z6c75XijMiIoXxjhPQLX_go4va96qfAN3h0yPkQInkzAZwpIy2IUOY3KOznr11ag27o09RMskWh9bV41hlqzrcNT_p3bRxdEqZRcjpIirH03FyC-slrF9aLDsWnayCM/s1600/2-Complier-Vs-Interpreter-Difference-between-Compiler-and-Interpreter.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="565" data-original-width="1600" height="141" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhhJy0K3zbi4465z6c75XijMiIoXxjhPQLX_go4va96qfAN3h0yPkQInkzAZwpIy2IUOY3KOznr11ag27o09RMskWh9bV41hlqzrcNT_p3bRxdEqZRcjpIirH03FyC-slrF9aLDsWnayCM/s400/2-Complier-Vs-Interpreter-Difference-between-Compiler-and-Interpreter.jpg" width="400" /></a></div> <div> <div> <b><br /></b></div> <div> <b>It is important to understand that a computer language defines the nature of a program and not the way that the program will be executed. There are two general methods by which a program can be executed. It can be compiled, or it can be interpreted. Although programs written in any computer language can be compiled or interpreted, some languages are designed more for one form of execution than the other. For example, Java was designed to be interpreted, and C was designed to be compiled. However, in the case of C, it is important to understand that it was specifically optimized as a compiled language. Although C interpreters have been written and are available in some environments (especially as debugging aids or experimental platforms like the interpreter developed in Part Six of this book), C was developed with compilation in mind. Therefore, you will almost certainly be using a C compiler and not a C interpreter when developing your C programs. Since the difference between a compiler and interpreter may not be clear to all readers, the following brief description will clarify matters.</b></div> <div> <b>In its simplest form, an interpreter reads the source code of your program one line at a time, performing the specific instructions contained in that line. This is the way earlier versions of BASIC worked. In languages such as Java, a program's source code is first converted into an intermediary form that is then interpreted. In either case, a run-time interpreter is still required to be present to execute the program.</b></div> <div> <b>A compiler reads the entire program and converts it into object code, which is a translation of the program's source code into a form that the computer can execute directly. Object code is also referred to as binary code or machine code. Once the program is compiled, a line of source code is no longer meaningful in the execution of your program.</b></div> <div> <br /></div> <div> <b>In general, an interpreted program runs slower than a compiled program. Remember, a compiler converts a program's source code into object code that a computer can execute directly. Therefore, compilation is a one-time cost, while interpretation incurs an overhead each time a program is run.</b></div> <div> <b>The Form of a C Program</b></div> <div> <b>Table 1-2 lists the 32 keywords defined by the C89 standard. These are also the C keywords that form the C subset of C++. Table 1-3 shows the keywords added by C99. The keywords, combined with the formal C syntax, form the C programming language.</b></div> <div> <b>In addition to the standard keywords, many compilers add nonstandard keywords that better exploit their operating environment. For example, several compilers include keywords to manage the memory organization of the 8086 family of processors, to support interlanguage programming, and to access interrupts. Here is a list of some commonly used extended keywords:</b></div> <div> <b>asm _ds huge pascal</b></div> <div> <b>cdecl _es interrupt _ss</b></div> <div> <b>_cs far near</b></div> <div> <b> </b></div> <div> <b>Your compiler may also support other extensions that help it take better advantage of its specific environment.</b></div> <div> <b>auto double int struct break else long switch case enum register typedef char extern return union const float short unsigned continue for signed void default goto sizeof volatile do if static while </b></div> </div> <div> <h3 style="text-align: left;"> <b>The Library and Linking:- </b></h3> <div style="font-weight: bold;"> Technically speaking, you can create a useful, functional C program that consists solely of statements involving only the C keywords. However, this is quite rare because C does not provide keywords that perform such things as input/output (I/O) operations, high-level mathematical computations, or character handling. As a result, most programs include calls to various functions contained in C's standard library.</div> <div style="font-weight: bold;"> All C compilers come with a standard library of functions that perform most commonly needed tasks. Standard C specifies a minimal set of functions that will be supported by all compilers. However, your compiler will probably contain many other functions. For example, the standard library does not define any graphics functions, but your compiler will probably include some.</div> <div style="font-weight: bold;"> When you call a library function, the C compiler ''remembers" its name. Later, the linker combines the code you wrote with the object code already found in the standard library. This process is called linking. Some compilers have their own linker, while others use the standard linker supplied by your operating system.</div> <div style="font-weight: bold;"> The functions in the library are in relocatable format. This means that the memory addresses for the various machine-code instructions have not been absolutely defined— only offset information has been kept. When your program links with the functions in the standard library, these memory offsets are used to create the actual addresses used. Several technical manuals and books explain this process in more</div> <h3 style="font-weight: bold; text-align: left;"> <br />Compiling a C Program:</h3> <div style="font-weight: bold;"> <div> Creating an executable form of your C program consists of these three steps:</div> <div> 1. Creating your program</div> <div> 2. Compiling your program</div> <div> 3. Linking your program with whatever functions are needed from the library</div> <div> Today, most compilers supply integrated programming environments that include an editor. Most also include stand-alone compilers. For stand-alone versions, you must have a separate editor to create your program. In either case, be careful: Compilers only accept standard text files for input. For example, your compiler will not accept files created by certain word processors because they contain control codes and nonprinting characters.</div> <div> The exact method you use to compile your program will depend upon what compiler you are using. Also, how linking is accomplished will vary between compilers and environments; for example, it may be included as part of the compiler or as a stand-alone application. Consult your compiler's documentation for details.</div> <h3 style="text-align: left;"> C's Memory Map:</h3> <div> A compiled C program creates and uses four logically distinct regions of memory. The first region is the memory that actually holds the program's executable code. The next region is memory where global variables are stored. The remaining two regions are the stack and the heap. The stack is used for a great many things while your program executes. It holds the return addresses of function calls, arguments to functions, and local variables. It will also save the current state of the CPU. The heap is a region of free memory that your program can use via C's dynamic memory allocation functions.</div> <div> <br /></div> </div> </div> </div>

Compilers vs. Interpreters It is important to understand that a computer language defines the nature of a program and not the way t...

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