Types of Literals in C/C++ with Examples
The values assigned to each constant variable are referred to as the literals. Generally, both terms, constants, and literals are used interchangeably.
For example, “const int = 5;“, is a constant expression and the value 5 is referred to as a constant integer literal. There are 4 types of literal in C and five types of literal in C++.
These are used to represent and store the integer values. Integer literals are expressed in two types i.e.
A) Prefixes: The Prefix of the integer literal indicates the base in which it is to be read.
0x10 = 16
Because 0x prefix represents a HexaDecimal base. So 10 in HexaDecimal is 16 in Decimal. Hence the value 16.
There are basically represented in 4 types.
a. Decimal-literal(base 10): A non-zero decimal digit followed by zero or more decimal digits(0, 1, 2, 3, 4, 5, 6, 7, 8, 9).
b. Octal-literal(base 8): a 0 followed by zero or more octal digits(0, 1, 2, 3, 4, 5, 6, 7).
045, 076, 06210
c. Hex-literal(base 16): 0x or 0X followed by one or more hexadecimal digits(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, A, b, B, c, C, d, D, e, E, f, F).
0x23A, 0Xb4C, 0xFEA
d. Binary-literal(base 2): 0b or 0B followed by one or more binary digits(0, 1).
B) Suffixes: The Prefix of the integer literal indicates the type in which it is to be read.
indicates a long long integer value 12345678901234 because of the suffix LL
These are represented in many ways according to their data types.
- int: No suffix is required because integer constant is by default assigned as an int data type.
- unsigned int: character u or U at the end of an integer constant.
- long int: character l or L at the end of an integer constant.
- unsigned long int: character ul or UL at the end of an integer constant.
- long long int: character ll or LL at the end of an integer constant.
- unsigned long long int: character ull or ULL at the end of an integer constant.
2) Floating-Point Literals
These are used to represent and store real numbers. The real number has an integer part, real part, fractional part, and exponential part. The floating-point literals can be stored either in decimal form or exponential form. While representing the floating-point decimals one must keep two things in mind to produce valid literal:
- In the decimal form, one must include the decimal point, exponent part, or both, otherwise, it will lead to an error.
- In the exponential form, one must include the integer part, fractional part, or both, otherwise, it will lead to an error.
Few floating-point literal representations are shown below:
Valid Floating Literals:
10.125 1.215-10L 10.5E-3
Invalid Floating Literals:
123E 1250f 0.e879
Floating point literal: 4.14
3) Character Literal
This refers to the literal that is used to store a single character within a single quote. To store multiple characters, one needs to use a character array. Storing more than one character within a single quote will throw a warning and display just the last character of the literal. It gives rise to the following two representations:
A. char type: This is used to store normal character literal or the narrow-character literals. This is supported by both C and C++.
// For C char chr = 'G'; // For C++ char chr = 'G';
B. wchar_t type: This literal is supported only in C++ and not in C. If the character is followed by L, then the literal needs to be stored in wchar_t. This represents a wide-character literal.
// Not Supported For C // For C++ wchar_t chr = L'G';
Character Literal: A
Escape Sequences: There are various special characters that one can use to perform various operations.
4) String Literals
String literals are similar to that character literals, except that they can store multiple characters and uses a double quote to store the same. It can also accommodate the special characters and escape sequences mentioned in the table above.
// For C char stringVal = "GeeksforGeeks"; // For C++ string stringVal = "GeeksforGeeks"
Welcome To Geeks For Geeks
5) Boolean Literals
This literal is provided only in C++ and not in C. They are used to represent the boolean datatypes. These can carry two values:
- true: To represent True value. This must not be considered equal to int 1.
- false: To represent False value. This must not be considered equal to int 0.
isTrue? 1 isFalse? 0
Related Articles on Constants/Literals in C/C++:
- User-Defined Literals.
- Raw string literal in C++
- Octal literals in C
- Compound Literals in C
- Type difference of character literals C++.