C++ Operators & Tokens

C++ Tokens & Operators.

* Before deep dive into the C++ Operators, let's revise all the C++ tokens for better understanding.

C++ Tokens

In C++, a token is the smallest individual unit in a program that has a specific meaning to the compiler. C++ programs are composed of various types of tokens. The basic categories of tokens in C++ include:

Keywords: These are reserved words that have special meanings in C++. Examples include 'int', 'double', 'if', 'else', 'while', and so on.

Identifiers: These are names given to various program elements such as variables, functions, arrays, etc. Identifiers must follow certain rules, such as starting with a letter, being composed of letters, digits, and underscores.

Literals: Represent constant values used in the program. Examples include integer literals (42), floating-point literals (3.14), character literals ('A'), and string literals ("Hello").

Operators: Symbols that perform operations on one or more operands. Examples include '+', '-', '*', '/', '==', '!=', '&&', etc.

Punctuators: These are characters that have special meanings in C++, such as braces '{}', parentheses '()', commas ',', and semicolons ';'.

Comments: Used for adding remarks or explanations in the code. C++ supports both single-line comments ('//') and multi-line comments ('/* */').

Preprocessor Directives: Lines in the code that start with '#' and are processed by the preprocessor before compilation. Examples include '#include', '#define', etc.

Whitespace: Spaces, tabs, and newline characters that separate tokens but are otherwise ignored by the compiler.

C++ Operators

C++ operators are symbols or keywords used to perform operations on variables and values. They are the building blocks of expressions and statements in C++. Here are some of the key categories of operators:

Arithmetic Operators:

These operators are used to perform basic arithmetic operations.

Operators Meanings Examples Results
+ Addition: Adds two operands. 5+2 7
- Subtraction: Subtracts the right operand from the left operand. 5-2 3
* Multiplication: Multiplies two operands. 5*2 10
/ Division: Divides the left operand by the right operand. 5/2 2
% Modulus: Computes the remainder of the division of the left operand by the right operand. 5%2 1

Syntax:

int a = 5, b = 2;
int sum = a + b;    // sum = 7
int difference = a - b; // difference = 3
int product = a * b; // product = 10
int quotient = a / b; // quotient = 2
int remainder = a % b; // remainder = 1

Relational Operators:

These operators are used for comparing two values.

Operators Meanings Examples Results
== Equal to: Checks if two operands are equal. 5==2 false
!= Not equal to: Checks if two operands are not equal. 5!=2 true
> Greater than: Checks if the left operand is greater than the right operand. 5>2 true
< Less than: Checks if the left operand is less than the right operand. 5<2 false
>= Greater than or equal to: Checks if the left operand is greater than or equal to the right operand. 5>=2 true
<= Less than or equal to: Checks if the left operand is less than or equal to the right operand. 5<=2 false

Syntax:

int x = 5, y = 10;
bool isEqual = (x == y); // false
bool isNotEqual = (x != y); // true
bool isLessThan = (x < y); // true
bool isGreaterThan = (x > y); // false
bool isLessThanOrEqual = (x <= y); // true
bool isGreaterThanOrEqual = (x >= y); // false

Logical Operators:

These operators are used to perform logical operations.

Operators Meanings Examples Results
&& Logical AND: Returns true if both operands are true. (5<2)&&(5>3) false
|| Logical OR: Returns true if at least one operand is true. (5<2)||(5>3) true
! Logical NOT: Returns true if the operand is false, and false if the operand is true. !(5>2) true

Syntax:

bool condition1 = true, condition2 = false;
bool resultAnd = (condition1 && condition2); // false
bool resultOr = (condition1 || condition2); // true
bool resultNot = !condition1; // false

Assignment Operators:

These operators are used to perform logical operations.

i = 5;
Operators Meanings Examples Results
= Assignment: Assigns the value of the right operand to the left operand. j = 2;

i = j;
Now 'i' value is '2'
+= Add and assign: Adds the right operand to the left operand and assigns the result to the left operand. i+=10 15
-= Subtract and assign): Subtracts the right operand from the left operand and assigns the result to the left operand. i-=10 -5
*= Multiply and assign: Multiplies the left operand by the right operand and assigns the result to the left operand. i*=10 50
/= Divide and assign: Divides the left operand by the right operand and assigns the result to the left operand. i/=10 0
%= Modulus and assign: Computes the modulus of the left operand with the right operand and assigns the result to the left operand. i%=10 5

Syntax:

int num = 10;
num += 5; // num is now 15 (num = num + 5)
num -= 3; // num is now 12 (num = num - 3)
num *= 2; // num is now 24 (num = num * 2)
num /= 4; // num is now 6 (num = num / 4)
num %= 2; // num is now 0 (num = num % 2)

Increment and Decrement Operators:

These operators are used to increment (++) or decrement (--) a variable by 1. For example, ++ is used to increase, and -- is used to reduce the value of an integer or char variable.

Syntax:

int count = 5;
count++; // Increment count by 1 (count is now 6)
count--; // Decrement count by 1 (count is now 5 again)

Bitwise Operators:

These operators perform bitwise operations on integer types, and Bitwise operators are used for low-level operations, such as bit manipulation.

Operators Meanings
<< Left shift: Shifts the bits to left.
>> Right shift: Shifts the bits to right.
~ Bitwise NOT: Bitwise inversion (one's complement).
& Bitwise AND: Bitwise logical and.
| Bitwise NOT: Bitwise logical or.
^ Bitwise XOR: Bitwise logical exclusive or.

Syntax:

int a = 5, b = 3;
int bitwiseAnd = a & b; // 1 (binary: 0101 & 0011 = 0001)
int bitwiseOr = a | b; // 7 (binary: 0101 | 0011 = 0111)
int bitwiseXor = a ^ b; // 6 (binary: 0101 ^ 0011 = 0110)
int bitwiseNot = ~a; // -6 (bitwise NOT of 5 is -6 in two's complement)

* Let's show an example of bitwise operators in C language.

Conditional (Ternary) Operator:

Conditional operator is used to check a condition and select a value depending on the condition. Normally the selected value will be assigned to a variable which ha the following form.

Syntax:

int x = 5, y = 10;
int max = (x > y) ? x : y; // max is assigned the larger of x and y

Comma Operator:

The comma operator in C++ is a binary operator that evaluates two expressions and returns the result of the second expression. It is often used in contexts where multiple expressions are allowed, but only a single expression is expected. The syntax for the comma operator is simply a comma (',').

Syntax:

int expr1, expr2;

Note: Here, 'expr1' is evaluated first, followed by 'expr2'. The result of the entire expression is the result of 'expr2'. The value of 'expr1' is essentially discarded.

What is New?

We have just updated this website & still working on adding new content & updating existing features.