Numeric literals in decimal notation or E exponent notation are treated as double values. Floating point literals are often called floating point constants. Many compilers will issue a warning if you assign a floating point constant to a float variable since you are assigning a double to a float so the number may be truncated. When you assign a floating point value literal or variable to an integer variable, the decimal part of the number is discarded.
The char data type is used for single characters. A char literal is a single character enclosed in single quotes. A string is sequence of characters. However, the standard library defines a string class allowing programmers to create string variables.
String literals can include spaces and escape sequences. In our discussion of variables and data types, we have shown a lot of examples of variable initialization.
The data that operators work on are called operands. The assignment operator requires two operands. The left operand must be a location in memory whose contents can be changed such as a variable. You will sometimes see references to l-value or lvalue in compiler error messages.
When you see this, your left hand operand does not refer to a memory location whose contents can be changed. 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. They are arithmetic types and are further classified into: a integer types and b floating-point types.
They are again arithmetic types and they are used to define variables that can only assign certain discrete integer values throughout the program. The array types and structure types are referred collectively as the aggregate types.
The type of a function specifies the type of the function's return value. We will see the basic types in the following section, where as other types will be covered in the upcoming chapters. To get the exact size of a type or a variable on a particular platform, you can use the sizeof operator.
The expressions sizeof type yields the storage size of the object or type in bytes. Given below is an example to get the size of various type on a machine using different constant defined in limits. Note: integer arithmetic is defined differently for the signed and unsigned integer types.
See arithmetic operators , in particular integer overflows. Note: this allows the extreme case in which bytes are sized 64 bits, all types including char are 64 bits wide, and sizeof returns 1 for every type. The following three types and their cv-qualified versions are collectively called floating-point types.
Floating-point types may support special values :. Some operations on floating-point numbers are affected by and modify the state of the floating-point environment most notably, the rounding direction.
Implicit conversions are defined between real floating types and integer types. Create account Log in. Namespaces Page Discussion. Views View Edit History. From cppreference. Keywords Escape sequences. Namespace declaration. Namespace aliases. Fundamental types Enumeration types Function types. Compound types Union types. Default initialization Value initialization Zero initialization Copy initialization Direct initialization.
Expressions Value categories Order of evaluation. Operators Operator precedence. Class declaration Constructors this pointer. Access specifiers friend specifier. Class template Function template. Inline assembly. Basic Concepts language keywords phases of translation comments the main function names and identifiers types fundamental types objects scope object lifetime storage duration and linkage definitions and ODR name lookup qualified name lookup unqualified name lookup the as-if rule undefined behavior memory model.
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