Expressions
Expressions Vs Statements
// Statements
int total_marks = pyhsics + chem + math; // statements
x = y = z;
// Expressions
int x = 10; // 10 is a expression
int y = 20, z = 30;
x = y = z + 10;- Any variable name (x, y, z, …), constant, or literal is an expression.
- One or more expressions combined by an operator constitute an expression, e.g., x + y or x * y + z
In C++, assignment is also an expression, e.g., x = y + z. As a consequence, it can be used within another assignment: x2 = x = y + z. Assignments are evaluated from right to left.
Statements
Any of the expressions above followed by a semicolon is a statement.
The variable and constant declarations we have seen before are also statements. As the initial value of a variable or constant, we can use any expression.
A single semicolon is an empty statement, and we can thus put as many semicolons after an expression as we want.
int marks = 10 // statement
5 + 3 // expression
5 + 3; // statement
int z = 5 + 3; // statement
int total = marks; // statement
// Control Statements
if (...){
}Operators
Arithmetic Operators
Relational Operators
A relational operator is used to check the relationship between two operands.
| Operator | Function |
|---|---|
| == | isEqual to |
| != | Not Equal to |
| > | Greater than |
| < | Lesser than |
| >= | Greater than or Equal to |
| ⇐ | Lesser than or Equal to |
Logical Operators
Logical operators are used to check whether an expression is true or false. If the expression is true, it returns 1 whereas if the expression is false, it returns 0.
| Operator | Function |
|---|---|
| && | Logical AND |
| || | Logical OR |
| ! | Logical NOT |
Bitwise Operators
In C++, bitwise operators are used to perform operations on individual bits. They can only be used alongside char and int data types.
| Operator | Function |
|---|---|
| & | Binary AND |
| | | Binary OR |
| ^ | Binary XOR (Exclusive OR) |
| ~ | Binary one compliment (Flip all bits of a number) |
| << | Left Shift |
| >> | Right Shift |
Assignment Operators
Also known as compound assignment operators (combine binary operator with assignment operator).
| Operator | Function |
|---|---|
| = | Assignment |
| += | Compound Addition |
| -= | Compound Subtraction |
| *= | Compound Multiplication |
| /= | Compound Division |
| %= | Compound Modulo |
Misc Operators
Here’s a list of some other common operators available in C++.
| Operator | Function |
|---|---|
| sizeof | returns size of datatype |
| ?: | Ternary operator |
| & | Address of operator |
| . | Dot operator |
| * | Dereference operator |
| → | Access members of objects |
Increment Decrement
Arithmetic operators are used to perform arithmetic operations on variables and data.
| Operator | Function |
|---|---|
| ++ | Increment |
| — | Decrement |
int a = 10;
a++; // postincrement
++a; // preincrement
a--; // postdecrement
--a; // predecrementAssociativity & Precedence
- Pending