Expression evaluation in C
Expression Evaluation in C
In c language expression evaluation is mainly depends on priority and associativity. An expression is a sequence of operands and operators that reduces to a single value. For example, the expression, 10+15 reduces to the value of 25.An expression is a combination of variables constants and operators written according to the syntax of C language. every expression results in some value of a certain type that can be assigned to a variable.
Priority
This represents the evaluation of expression starts from "what" operator.
Associativity
It represents which operator should be evaluated first if an expression is containing more than one operator with same priority.
| Operator | Priority | Associativity |
|---|---|---|
| {}, (), [] | 1 | Left to right |
| ++, --, ! | 2 | Right to left |
| *, /, % | 3 | Left to right |
| +, - | 4 | Left to right |
| <, <=, >, >=, ==, != | 5 | Left to right |
| && | 6 | Left to right |
| || | 7 | Left to right |
| ?: | 8 | Right to left |
| =, +=, -=, *=, /=, %= | 9 | Right to left |
Example 1:
Example 2:
Types of Expression Evaluation in C
Based on the operators and operators used in the expression, they are divided into several types. Types of Expression Evaluation in C are:
- Integer expressions – expressions which contains integers and operators
- Real expressions – expressions which contains floating point values and operators
- Arithmetic expressions – expressions which contain operands and arithmetic operators
- Mixed mode arithmetic expressions – expressions which contain both integer and real operands
- Relational expressions – expressions which contain relational operators and operands
- Logical expressions – expressions which contain logical operators and operands
- Assignment expressions and so on… – expressions which contain assignment operators and operands