Logical Not ! operator in C with Examples

! is a type of Logical Operator and is read as “NOT” or “Logical NOT“. This operator is used to perform “logical NOT” operation, i.e. the function similar to Inverter gate in digital electronics.

Syntax:

!Condition

// returns true if the conditions is false
// else returns false

Below is an example to demonstrate ! operator:

Example:

// C program to demonstrate working
// of logical NOT '!' operators

#include <stdio.h>

int main()
{

    // Taking a variable a
    // and set it to 0 (false)
    int a = 0;

    // logical NOT example

    // Since 0 is considered to be false
    // !a will yield true
    if (!a)
        printf("Condition yielded True\n");
    else
        printf("Condition yielded False\n");

    // set a to non-zero value (true)
    a = 1;

    // Since a non-zero value is considered to be true
    // !a will yield false
    if (!a)
        printf("Condition yielded True\n");
    else
        printf("Condition yielded False\n");

    return 0;
}

Output:

Condition yielded True
Condition yielded False