Preview
Logical Operators in C
There are three logical operators.
1. Logical And(&&)
Logical And operator is represented as double ampersand sign (&&). It is used to combine two relational expressions. If any input is 0, output is 0. If all inputs are 1, output is 1.
Truth table for Logical AND operator
| Input1 | Input2 | Output |
| 0 | 0 | 0 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 1 |
Example
110 >12 && 110>15 = 1
110 >12 && 110<15 = 0
2. Logical OR(||)
Logical OR operator is represented as double pipe sign (||). It is used to combine two relational expressions. If any input is 1, output is 1. If all inputs are 0, output is 0.
Truth table for Logical OR operator
| Input1 | Input2 | Output |
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 1 |
Example
110 >12 || 110>15 = 1
110 <12 || 110<15 = 0
3. Logical NOT(!)
Logical NOT operator is represented as sign of exclamation(!). If input is 0, output is 1 and vice versa.
Truth table for Logical NOT operator
| Input | Output |
| 0 | 1 |
| 1 | 0 |
Example
!(110 >12 && 110>15) = 0
!(110<15) = 1
| Program to demonstrate logical operators. |
Output (Line Wise) |
| #include<stdio.h> #include<conio.h> int main() { int a,b,c; |
|
| a=110 | |
| b=12 | |
| printf(”\n%d”, (a>0 && b>0); | 1 |
| printf(”\n%d”, (a<0 && b>0); | 0 |
| printf(”\n%d”, (a>0 || b<0); | 1 |
| printf(”\n%d”, (a<0 && b<0); | 0 |
| printf(”\n%d”, !(a>0); | 0 |
| printf(”\n%d”, !(a<0 && b>0); | 1 |
| getch(); return (0); } |