In deze sectie wordt de logische NOT (!) operator in de programmeertaal C besproken. Zoals we al weten, wordt de logische operator gebruikt om de logische bewerking uit te voeren door twee of meer voorwaarden voor de gegeven expressies te combineren. Als de logische voorwaarden van de operanden waar zijn, retourneert de operator ware Booleaanse waarden of 1. Anders retourneert de operator een valse Booleaanse waarde of 0. De logische operators worden in drie delen ingedeeld: Logische AND-, Logische OR- en Logische NOT-operatoren.
De logische AND-operator wordt gebruikt om te controleren of de voorwaarden van twee of meer operanden die overblijven waar zijn in een bepaalde expressie; de AND-operator retourneert een waarde waar of niet nul (1). Anders retourneert het een false- of 0-waarde. We kunnen dus zeggen dat de logische AND-operator alleen kan presteren in een expressie als de voorwaarden van beide operanden waar zijn, en als een voorwaarde niet waar is, retourneert deze 0. De logische AND-operator wordt weergegeven als het dubbele ampersand '&&'-symbool.
Syntaxis:
(A > b && b > c)
De logische OR-operator wordt gebruikt om de voorwaarden van beide operanden (A en B) te controleren, en als een van de operanden of expressies waar is, retourneert de operator een echte Booleaanse waarde. Op dezelfde manier retourneert het een onwaar- of nulwaarde als geen van de expressies waar is. De logische OR-operator wordt aangeduid als de dubbele pipe '||' symbool.
Syntaxis:
(A > B) || (A <c) < pre> <h3>Logical NOT operator</h3> <p>The logical NOT operator is represented as the '!' symbol, which is used to reverse the result of any given expression or condition. If the result of an expression is non-zero or true, the result will be reversed as zero or false value. Similarly, if the condition's result is false or 0, the NOT operator reverses the result and returns 1 or true.</p> <p>For example, suppose the user enters a non-zero value is 5, the logical NOT (!) operator returns the 0 or false Boolean value. And if the user enters a zero (0) value, the operator returns the true Boolean value or 1. </p> <p> <strong>Syntax of the logical NOT operator</strong> </p> <pre> ! (condition); // It '!' represents the NOT operator </pre> <p>Here, the '!' symbol represents the logical NOT operator, which inverses the result of the given condition.</p> <h3>The truth table of the logical NOT operator:</h3> <p>Following is the truth table of the logical not operator in C</p> <pre> condition !(condition) 1 0 0 1 </pre> <h3>Example 1: Program to use the logical NOT operator in C</h3> <p>Let's create a simple program to reverse the given condition of the operands in the C programming language.</p> <pre> /* demonstration the use of the logical not operator in C. */ #include #include int main () { // declare an initialize x variable int x = 5; // display the result generated using the NOT (!) operator printf (' The return value = %d
', ! (x == 5)); printf (' The return value = %d
', ! (x != 5)); printf (' The return value = %d
', ! (x >= 3)); printf (' The return value = %d
', ! (x <3)); return 0; } < pre> <p> <strong>Output:</strong> </p> <pre> The return value = 0 The return value = 1 The return value = 0 The return value = 1 </pre> <p>In the above program, we use the NOT (!) operator to reverse the result of the various expression, such as the condition of the variable x is equal to 5, which is true. Still, the NOT operator reverses the result and returns 0. Similarly, we defined the condition (x!=5), but the logical operator changed its result and returned 1 and so on.</p> <h3>Example 2: Program to input a number to perform the logical NOT operator</h3> <p>Let's create a simple program to get the reverse result of an integer number using the logical NOT (!) operator in the C programming language.</p> <pre> /* demonstration the use of the logical not operator in C. */ #include #include int main () { // declare an initialize x variable int x, n; printf (' Enter the number: '); scanf ('%d', &x); n = !x; // use logical not operator to reverse the condition printf (' The result of x: %d', n); // display the result return 0; } </pre> <p> <strong>Output:</strong> </p> <pre> Enter the number: 7 The result of x: 0 </pre> <p>In the above program, we input an integer number 7 from the user and store it into x variable. After that, the logical NOT (!) operator reverses the value of x (non-zero) and returns zero (0) to print the result of x.</p> <p> <strong>2<sup>nd</sup> execution:</strong> </p> <pre> Enter the number: 0 The result of x: 1 </pre> <p>Similarly, we input zero (0) from the user and use the logical NOT (!) operator to reverse the value of x to a non-zero value, which is 1.</p> <h3>Example 3: Program to find the leap year using the logical AND (&&), OR (||), and NOT (!) operator</h3> <p>Let's write a simple program to check whether the given year is a leap or not using the logical AND (&&), logical OR (||), and the logical NOT (!) operator in the C language.</p> <pre> #include #include int main () { int yr; // declare int type variable printf (' Enter the year: '); scanf ('%d', &yr); // use the if..else statement to check the condition /* '&&' (AND) operator to validate both operand, '||' (OR) operator check ny given expressions are true, '!' (NOT) check the result of (yr % 100 != 0). */ if ( (yr % 400 == 0) || (yr % 4 == 0 && yr % 100 != 0)) { printf (' %d is a leap year.
', yr); } else { printf (' %d is not a leap year.
', yr); } return 0; } </pre> <p> <strong>Output:</strong> </p> <pre> Enter the year: 2020 2020 is a leap year. </pre> <p>In the above program, we enter 2020 and then check the given year by defining the if...else statement. In this statement, we defined two conditions;</p> <ol class="points"> <li>The given year is divided by 400, which is equal to 0. And then, we use the logical OR operator to check whether the left or right operand condition is true.</li> <li>In the second condition, the given year is divided by 4 and 100. But when we divide 2020 with 4, which is equal to 0. Similarly, we divide the year 2020 by 100, which is also not equal to 0. So, both the conditions are true that display the '2020 is a leap year'.</li> <li>But when we enter the year 2021, it prints the given result '2021 is not a leap year'.</li> </ol> <p> <strong>2<sup>nd</sup> execution:</strong> </p> <pre> Enter the year: 2021 2021 is not a leap year. </pre> <p> <strong>Example 4: Program to check different conditions using the AND, OR, and the NOT logical operator</strong> </p> <p>Let's write a program to demonstrate the multiple conditions of the given operands using the AND, OR, and the NOT logical operator in C.</p> <pre> /* program to check the various condition using the logical NOT operator in c. */ #include #include int main () { // declare and initialize variables int a = 20, b = 15; int n1 = 15, n2 = 17; // use logical 'AND' and logical 'NOT' operator if (a > b && a != 0) { printf (' The AND (&&) operator said: Both conditions are true.
'); } // use logical 'OR' and logical 'NOT' operator if (n1 > n2 || n2 != 15) if ( ! (a > b && a != 0 )) { printf (' The NOT (!) operator: Here both conditions are true.
'); } else { printf (' The NOT (!) operator: Here, both conditions are true. ' ' But, the status of the condition is reversed as false.
'); } return 0; } </pre> <p> <strong>Output:</strong> </p> <pre> The AND (&&) operator is said: Both conditions are true. The OR (||) operator is said: Only one condition is true. The NOT (!) operator: Here, both conditions are true. But, the status of the condition is reversed as false. </pre> <hr></3));></pre></c)> Hier de '!' symbool vertegenwoordigt de logische NOT-operator, die het resultaat van de gegeven voorwaarde omkeert.
De waarheidstabel van de logische NOT-operator:
Hieronder volgt de waarheidstabel van de logische not-operator in C
condition !(condition) 1 0 0 1
Voorbeeld 1: Programma om de logische NOT-operator in C te gebruiken
Laten we een eenvoudig programma maken om de gegeven toestand van de operanden in de programmeertaal C om te keren.
/* demonstration the use of the logical not operator in C. */ #include #include int main () { // declare an initialize x variable int x = 5; // display the result generated using the NOT (!) operator printf (' The return value = %d
', ! (x == 5)); printf (' The return value = %d
', ! (x != 5)); printf (' The return value = %d
', ! (x >= 3)); printf (' The return value = %d
', ! (x <3)); return 0; } < pre> <p> <strong>Output:</strong> </p> <pre> The return value = 0 The return value = 1 The return value = 0 The return value = 1 </pre> <p>In the above program, we use the NOT (!) operator to reverse the result of the various expression, such as the condition of the variable x is equal to 5, which is true. Still, the NOT operator reverses the result and returns 0. Similarly, we defined the condition (x!=5), but the logical operator changed its result and returned 1 and so on.</p> <h3>Example 2: Program to input a number to perform the logical NOT operator</h3> <p>Let's create a simple program to get the reverse result of an integer number using the logical NOT (!) operator in the C programming language.</p> <pre> /* demonstration the use of the logical not operator in C. */ #include #include int main () { // declare an initialize x variable int x, n; printf (' Enter the number: '); scanf ('%d', &x); n = !x; // use logical not operator to reverse the condition printf (' The result of x: %d', n); // display the result return 0; } </pre> <p> <strong>Output:</strong> </p> <pre> Enter the number: 7 The result of x: 0 </pre> <p>In the above program, we input an integer number 7 from the user and store it into x variable. After that, the logical NOT (!) operator reverses the value of x (non-zero) and returns zero (0) to print the result of x.</p> <p> <strong>2<sup>nd</sup> execution:</strong> </p> <pre> Enter the number: 0 The result of x: 1 </pre> <p>Similarly, we input zero (0) from the user and use the logical NOT (!) operator to reverse the value of x to a non-zero value, which is 1.</p> <h3>Example 3: Program to find the leap year using the logical AND (&&), OR (||), and NOT (!) operator</h3> <p>Let's write a simple program to check whether the given year is a leap or not using the logical AND (&&), logical OR (||), and the logical NOT (!) operator in the C language.</p> <pre> #include #include int main () { int yr; // declare int type variable printf (' Enter the year: '); scanf ('%d', &yr); // use the if..else statement to check the condition /* '&&' (AND) operator to validate both operand, '||' (OR) operator check ny given expressions are true, '!' (NOT) check the result of (yr % 100 != 0). */ if ( (yr % 400 == 0) || (yr % 4 == 0 && yr % 100 != 0)) { printf (' %d is a leap year.
', yr); } else { printf (' %d is not a leap year.
', yr); } return 0; } </pre> <p> <strong>Output:</strong> </p> <pre> Enter the year: 2020 2020 is a leap year. </pre> <p>In the above program, we enter 2020 and then check the given year by defining the if...else statement. In this statement, we defined two conditions;</p> <ol class="points"> <li>The given year is divided by 400, which is equal to 0. And then, we use the logical OR operator to check whether the left or right operand condition is true.</li> <li>In the second condition, the given year is divided by 4 and 100. But when we divide 2020 with 4, which is equal to 0. Similarly, we divide the year 2020 by 100, which is also not equal to 0. So, both the conditions are true that display the '2020 is a leap year'.</li> <li>But when we enter the year 2021, it prints the given result '2021 is not a leap year'.</li> </ol> <p> <strong>2<sup>nd</sup> execution:</strong> </p> <pre> Enter the year: 2021 2021 is not a leap year. </pre> <p> <strong>Example 4: Program to check different conditions using the AND, OR, and the NOT logical operator</strong> </p> <p>Let's write a program to demonstrate the multiple conditions of the given operands using the AND, OR, and the NOT logical operator in C.</p> <pre> /* program to check the various condition using the logical NOT operator in c. */ #include #include int main () { // declare and initialize variables int a = 20, b = 15; int n1 = 15, n2 = 17; // use logical 'AND' and logical 'NOT' operator if (a > b && a != 0) { printf (' The AND (&&) operator said: Both conditions are true.
'); } // use logical 'OR' and logical 'NOT' operator if (n1 > n2 || n2 != 15) if ( ! (a > b && a != 0 )) { printf (' The NOT (!) operator: Here both conditions are true.
'); } else { printf (' The NOT (!) operator: Here, both conditions are true. ' ' But, the status of the condition is reversed as false.
'); } return 0; } </pre> <p> <strong>Output:</strong> </p> <pre> The AND (&&) operator is said: Both conditions are true. The OR (||) operator is said: Only one condition is true. The NOT (!) operator: Here, both conditions are true. But, the status of the condition is reversed as false. </pre> <hr></3));> In het bovenstaande programma gebruiken we de NOT (!) operator om het resultaat van de verschillende uitdrukkingen om te keren, bijvoorbeeld de voorwaarde van de variabele x is gelijk aan 5, wat waar is. Toch keert de NOT-operator het resultaat om en retourneert 0. Op dezelfde manier hebben we de voorwaarde gedefinieerd (x!=5), maar de logische operator heeft het resultaat gewijzigd en 1 geretourneerd, enzovoort.
Voorbeeld 2: Programma om een getal in te voeren om de logische NOT-operator uit te voeren
Laten we een eenvoudig programma maken om het omgekeerde resultaat van een geheel getal te krijgen met behulp van de logische NOT (!) operator in de programmeertaal C.
/* demonstration the use of the logical not operator in C. */ #include #include int main () { // declare an initialize x variable int x, n; printf (' Enter the number: '); scanf ('%d', &x); n = !x; // use logical not operator to reverse the condition printf (' The result of x: %d', n); // display the result return 0; } Uitgang:
Enter the number: 7 The result of x: 0
In het bovenstaande programma voeren we een geheel getal 7 van de gebruiker in en slaan dit op in de x-variabele. Daarna keert de logische operator NOT (!) de waarde van x (niet nul) om en retourneert nul (0) om het resultaat van x af te drukken.
2nlexecutie:
Enter the number: 0 The result of x: 1
Op dezelfde manier voeren we nul (0) in van de gebruiker en gebruiken we de logische NOT (!) operator om de waarde van x om te keren naar een waarde die niet nul is, namelijk 1.
Voorbeeld 3: Programma om het schrikkeljaar te vinden met behulp van de logische AND (&&), OR (||) en NOT (!) operator
Laten we een eenvoudig programma schrijven om te controleren of het gegeven jaar een sprong is of niet, met behulp van de logische AND (&&), logische OR (||) en de logische NOT (!) operator in de C-taal.
#include #include int main () { int yr; // declare int type variable printf (' Enter the year: '); scanf ('%d', &yr); // use the if..else statement to check the condition /* '&&' (AND) operator to validate both operand, '||' (OR) operator check ny given expressions are true, '!' (NOT) check the result of (yr % 100 != 0). */ if ( (yr % 400 == 0) || (yr % 4 == 0 && yr % 100 != 0)) { printf (' %d is a leap year.
', yr); } else { printf (' %d is not a leap year.
', yr); } return 0; } Uitgang:
Enter the year: 2020 2020 is a leap year.
In het bovenstaande programma voeren we 2020 in en controleren vervolgens het gegeven jaar door de if...else verklaring te definiëren. In deze verklaring hebben we twee voorwaarden gedefinieerd;
- Het gegeven jaar wordt gedeeld door 400, wat gelijk is aan 0. Vervolgens gebruiken we de logische OR-operator om te controleren of de linker- of rechteroperandvoorwaarde waar is.
- In de tweede voorwaarde wordt het gegeven jaar gedeeld door 4 en 100. Maar als we 2020 delen door 4, wat gelijk is aan 0. Op dezelfde manier delen we het jaar 2020 door 100, wat ook niet gelijk is aan 0. Dus beide de omstandigheden zijn waar en tonen aan dat '2020 een schrikkeljaar is'.
- Maar als we het jaar 2021 invoeren, wordt het gegeven resultaat weergegeven: '2021 is geen schrikkeljaar'.
2nlexecutie:
Enter the year: 2021 2021 is not a leap year.
Voorbeeld 4: Programma om verschillende voorwaarden te controleren met behulp van de logische operator AND, OR en NOT
Laten we een programma schrijven om de meerdere voorwaarden van de gegeven operanden te demonstreren met behulp van de logische operator AND, OR en NOT in C.
/* program to check the various condition using the logical NOT operator in c. */ #include #include int main () { // declare and initialize variables int a = 20, b = 15; int n1 = 15, n2 = 17; // use logical 'AND' and logical 'NOT' operator if (a > b && a != 0) { printf (' The AND (&&) operator said: Both conditions are true.
'); } // use logical 'OR' and logical 'NOT' operator if (n1 > n2 || n2 != 15) if ( ! (a > b && a != 0 )) { printf (' The NOT (!) operator: Here both conditions are true.
'); } else { printf (' The NOT (!) operator: Here, both conditions are true. ' ' But, the status of the condition is reversed as false.
'); } return 0; } Uitgang:
The AND (&&) operator is said: Both conditions are true. The OR (||) operator is said: Only one condition is true. The NOT (!) operator: Here, both conditions are true. But, the status of the condition is reversed as false.