There are two logical operators also available in C.
They are:-
Operator Meaning
&& and
|| or
The result of a logical and operation will be true only if both operands are true where as the result of a logical or operation will be true if either operand is true or if both operands are true. In other words the result of a logical or operation will be false only if both operands are false. Suppose i is an integer variable whose value is 7, f is a floating point variable whose value is
5.5 and C is a character variable that represents the character ‘w’, several complex logical expressions that make use of these variables are shown below:
| Expression | Interpretation | Value |
| | | |
| (i > = 6)&&(c = = ‘w‘) | true | 1 |
| (i >= 6)&&(c = = 119) | true | 1 |
| (f < 11) && (i > 100) | false | 0 |
| (c = ‘p‘) || ((i + f) < = 10) | true | 1 |
RELATIONAL AND LOGICAL OPERATORS
These are four relational operators in C.
They are:-
| Operator | Meaning |
| < | Less than |
| <= | Less than or equal to |
| > | Greater than |
| >= | Greater than or equal to |
EQUALITY OPERATORS
There are two equality operators in C which are as follows:-
| Operators | Meaning |
| = = | Equal to |
| ! = | Not equal to |
The six operators mentioned above are used to form logical expressions representing condi- tions that are either true or false.
The resulting expression will be of type integer, since true is represented by the integer value
1 and false is represented by the value 0.
e.g . Let us suppose i, j and k are integer variables whose values are 1,2 and 3 respectively. Several logical expressions involving these variables are shown below.
| Expression | Interpretation | Value |
| | | |
| i < j | true | 1 |
| (i + j) > = k | true | 1 |
| (j + k) > (i + 5) | false | 0 |
| k ! = 3 | false | 0 |
| j = = 2 | true | 1 |
