DATATYPES,KEYWORDS,FORMATSPECS[1].pptx
- 1. DATA TYPES, KEYWORDS, INPUT/OUTPUT AND FORMAT SPECIFIERS
- 2. DATA TYPES • Data types in c refer to an extensive system used for declaring variables or functions of different types. • The type of a variable determines how much space it occupies in storage and how the bit pattern stored is interpreted.
- 3. BASIC DATA TYPES • The basic data types are integer-based and floating-point based. C language supports both signed and unsigned literals. Data Types Memory Size unsigned signed char 1 byte 0 to 255 −128 to 127 short 2 byte 0 to 65,535 -32,768 to 32,767 int 2 byte 0 to 65,535 −32,768 to 32,767 float 4 byte 1.2E-38 to 3.4E+38 double 8 byte 2.3E-308 to 1.7E+308 long double 10 byte 3.4E-4932 to 1.1E+4932
- 4. VOID DATA TYPES • The void type specifies that no value is available. It is used in three kinds of situations − • Function returns as void: A function with no return value has the return type as void. For example, void exit (int status); • Function arguments as void: A function with no parameter can accept a void. For example, int rand(void); • Pointers to void: A pointer of type void * represents the address of an object, but not its type. For example, a memory allocation function void *malloc( size_t size ); returns a pointer to void which can be casted to any data type.
- 5. KEYWORDS • A keyword is a reserved word. You cannot use it as a variable name, constant name, etc. There are only 32 reserved words (keywords) in the C language.
- 6. INPUT AND OUTPUT • C language has standard libraries that allow input and output in a program. • The stdio.h or standard input output library in C that has methods for input and output. • scanf(): The scanf() method, in C, reads the value from the console as per the type specified. Syntax: scanf(“%X”, &variableOfXType); • printf(): The printf() method, in C, prints the value passed as the parameter to it, on the console screen. Syntax: printf(“%X”, variableOfXType);
- 7. FORMAT SPECIFIERS • The format specifiers are used in C for input and output purposes. • Using this concept the compiler can understand that what type of data is in a variable during taking input using the scanf() function and printing using printf() function. Format Specifier Type %c Character %d Signed integer %f Float values %l or %ld or %li Long %lf Double %s String %p Pointer