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Operador lógico NOT (!) en C

Esta sección analizará el operador lógico NOT (!) en el lenguaje de programación C. Como ya sabemos, el operador lógico se utiliza para realizar la operación lógica combinando dos o más condiciones en las expresiones dadas. Si las condiciones lógicas de los operandos son verdaderas, el operador devuelve valores booleanos verdaderos o 1. En caso contrario, devuelve un valor booleano falso o 0. Los operadores lógicos se clasifican en tres partes: Operadores lógicos AND, lógicos OR y lógicos NOT.

Operador lógico NOT (!) en C

El operador lógico Y se utiliza para comprobar que las condiciones de dos o más operandos que quedan son verdaderas en una expresión determinada; el operador AND devuelve un valor verdadero o distinto de cero (1). De lo contrario, devuelve un valor falso o 0. Entonces, podemos decir que el operador lógico AND solo puede funcionar en una expresión cuando las condiciones de ambos operandos son verdaderas, y si alguna condición no es verdadera, devuelve 0. El operador lógico AND se representa como el símbolo doble comercial '&&'.

Sintaxis:

 (A > b && b > c) 

El operador lógico OR se utiliza para verificar las condiciones de ambos operandos (A y B), y si uno de los operandos o expresiones es verdadero, el operador devuelve un valor booleano verdadero. De manera similar, si ninguna de las expresiones es verdadera, devuelve un valor falso o cero. El operador lógico OR se indica como la tubería doble '||' símbolo.

Sintaxis:

 (A &gt; B) || (A <c) < pre> <h3>Logical NOT operator</h3> <p>The logical NOT operator is represented as the &apos;!&apos; 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&apos;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 &apos;!&apos; represents the NOT operator </pre> <p>Here, the &apos;!&apos; 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&apos;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 (&apos; The return value = %d 
&apos;, ! (x == 5)); printf (&apos; The return value = %d 
&apos;, ! (x != 5)); printf (&apos; The return value = %d 
&apos;, ! (x &gt;= 3)); printf (&apos; The return value = %d 
&apos;, ! (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&apos;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 (&apos; Enter the number: &apos;); scanf (&apos;%d&apos;, &amp;x); n = !x; // use logical not operator to reverse the condition printf (&apos; The result of x: %d&apos;, 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 (&amp;&amp;), OR (||), and NOT (!) operator</h3> <p>Let&apos;s write a simple program to check whether the given year is a leap or not using the logical AND (&amp;&amp;), logical OR (||), and the logical NOT (!) operator in the C language.</p> <pre> #include #include int main () { int yr; // declare int type variable printf (&apos; Enter the year: &apos;); scanf (&apos;%d&apos;, &amp;yr); // use the if..else statement to check the condition /* &apos;&amp;&amp;&apos; (AND) operator to validate both operand, &apos;||&apos; (OR) operator check ny given expressions are true, &apos;!&apos; (NOT) check the result of (yr % 100 != 0). */ if ( (yr % 400 == 0) || (yr % 4 == 0 &amp;&amp; yr % 100 != 0)) { printf (&apos; %d is a leap year. 
&apos;, yr); } else { printf (&apos; %d is not a leap year. 
&apos;, 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 &apos;2020 is a leap year&apos;.</li> <li>But when we enter the year 2021, it prints the given result &apos;2021 is not a leap year&apos;.</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&apos;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 &apos;AND&apos; and logical &apos;NOT&apos; operator if (a &gt; b &amp;&amp; a != 0) { printf (&apos; The AND (&amp;&amp;) operator said: Both conditions are true. 
 &apos;); } // use logical &apos;OR&apos; and logical &apos;NOT&apos; operator if (n1 &gt; n2 || n2 != 15) if ( ! (a &gt; b &amp;&amp; a != 0 )) { printf (&apos; The NOT (!) operator: Here both conditions are true. 
 &apos;); } else { printf (&apos; The NOT (!) operator: Here, both conditions are true. &apos; &apos; But, the status of the condition is reversed as false. 
&apos;); } return 0; } </pre> <p> <strong>Output:</strong> </p> <pre> The AND (&amp;&amp;) 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)>

Aquí el '!' El símbolo representa el operador lógico NOT, que invierte el resultado de la condición dada.

La tabla de verdad del operador lógico NOT:

A continuación se muestra la tabla de verdad del operador lógico not en C.

 condition !(condition) 1 0 0 1 

Ejemplo 1: Programa para utilizar el operador lógico NOT en C

Creemos un programa simple para revertir la condición dada de los operandos en el lenguaje de programación C.

 /* 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 (&apos; The return value = %d 
&apos;, ! (x == 5)); printf (&apos; The return value = %d 
&apos;, ! (x != 5)); printf (&apos; The return value = %d 
&apos;, ! (x &gt;= 3)); printf (&apos; The return value = %d 
&apos;, ! (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&apos;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 (&apos; Enter the number: &apos;); scanf (&apos;%d&apos;, &amp;x); n = !x; // use logical not operator to reverse the condition printf (&apos; The result of x: %d&apos;, 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 (&amp;&amp;), OR (||), and NOT (!) operator</h3> <p>Let&apos;s write a simple program to check whether the given year is a leap or not using the logical AND (&amp;&amp;), logical OR (||), and the logical NOT (!) operator in the C language.</p> <pre> #include #include int main () { int yr; // declare int type variable printf (&apos; Enter the year: &apos;); scanf (&apos;%d&apos;, &amp;yr); // use the if..else statement to check the condition /* &apos;&amp;&amp;&apos; (AND) operator to validate both operand, &apos;||&apos; (OR) operator check ny given expressions are true, &apos;!&apos; (NOT) check the result of (yr % 100 != 0). */ if ( (yr % 400 == 0) || (yr % 4 == 0 &amp;&amp; yr % 100 != 0)) { printf (&apos; %d is a leap year. 
&apos;, yr); } else { printf (&apos; %d is not a leap year. 
&apos;, 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 &apos;2020 is a leap year&apos;.</li> <li>But when we enter the year 2021, it prints the given result &apos;2021 is not a leap year&apos;.</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&apos;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 &apos;AND&apos; and logical &apos;NOT&apos; operator if (a &gt; b &amp;&amp; a != 0) { printf (&apos; The AND (&amp;&amp;) operator said: Both conditions are true. 
 &apos;); } // use logical &apos;OR&apos; and logical &apos;NOT&apos; operator if (n1 &gt; n2 || n2 != 15) if ( ! (a &gt; b &amp;&amp; a != 0 )) { printf (&apos; The NOT (!) operator: Here both conditions are true. 
 &apos;); } else { printf (&apos; The NOT (!) operator: Here, both conditions are true. &apos; &apos; But, the status of the condition is reversed as false. 
&apos;); } return 0; } </pre> <p> <strong>Output:</strong> </p> <pre> The AND (&amp;&amp;) 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));>

En el programa anterior, utilizamos el operador NOT (!) para invertir el resultado de las distintas expresiones, como por ejemplo que la condición de la variable x sea igual a 5, lo cual es cierto. Aun así, el operador NOT invierte el resultado y devuelve 0. De manera similar, definimos la condición (x!=5), pero el operador lógico cambió su resultado y devolvió 1 y así sucesivamente.

Ejemplo 2: Programa para ingresar un número para realizar el operador lógico NOT

Creemos un programa simple para obtener el resultado inverso de un número entero usando el operador lógico NOT (!) en el lenguaje de programación C.

guardar desde
 /* demonstration the use of the logical not operator in C. */ #include #include int main () { // declare an initialize x variable int x, n; printf (&apos; Enter the number: &apos;); scanf (&apos;%d&apos;, &amp;x); n = !x; // use logical not operator to reverse the condition printf (&apos; The result of x: %d&apos;, n); // display the result return 0; } 

Producción:

 Enter the number: 7 The result of x: 0 

En el programa anterior, ingresamos un número entero 7 del usuario y lo almacenamos en la variable x. Después de eso, el operador lógico NOT (!) invierte el valor de x (distinto de cero) y devuelve cero (0) para imprimir el resultado de x.

2Dakota del Norteejecución:

 Enter the number: 0 The result of x: 1 

De manera similar, ingresamos cero (0) del usuario y usamos el operador lógico NOT (!) para invertir el valor de x a un valor distinto de cero, que es 1.

Ejemplo 3: Programa para encontrar el año bisiesto usando el operador lógico AND (&&), OR (||) y NOT (!)

Escribamos un programa simple para verificar si el año dado es bisiesto o no usando el operador lógico AND (&&), lógico OR (||) y lógico NOT (!) en el lenguaje C.

 #include #include int main () { int yr; // declare int type variable printf (&apos; Enter the year: &apos;); scanf (&apos;%d&apos;, &amp;yr); // use the if..else statement to check the condition /* &apos;&amp;&amp;&apos; (AND) operator to validate both operand, &apos;||&apos; (OR) operator check ny given expressions are true, &apos;!&apos; (NOT) check the result of (yr % 100 != 0). */ if ( (yr % 400 == 0) || (yr % 4 == 0 &amp;&amp; yr % 100 != 0)) { printf (&apos; %d is a leap year. 
&apos;, yr); } else { printf (&apos; %d is not a leap year. 
&apos;, yr); } return 0; } 

Producción:

 Enter the year: 2020 2020 is a leap year. 

En el programa anterior, ingresamos 2020 y luego verificamos el año dado definiendo la declaración if...else. En esta declaración, definimos dos condiciones;

  1. El año dado se divide por 400, que es igual a 0. Y luego, usamos el operador lógico OR para verificar si la condición del operando izquierdo o derecho es verdadera.
  2. En la segunda condición, el año dado se divide entre 4 y 100. Pero cuando dividimos 2020 entre 4, que es igual a 0. De manera similar, dividimos el año 2020 entre 100, que tampoco es igual a 0. Entonces, ambos Se cumplen las condiciones que muestran el '2020 es un año bisiesto'.
  3. Pero cuando ingresamos al año 2021, se imprime el resultado dado '2021 no es un año bisiesto'.

2Dakota del Norteejecución:

 Enter the year: 2021 2021 is not a leap year. 

Ejemplo 4: Programa para verificar diferentes condiciones usando el operador lógico AND, OR y NOT

Escribamos un programa para demostrar las múltiples condiciones de los operandos dados usando el operador lógico AND, OR y NOT en 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 &apos;AND&apos; and logical &apos;NOT&apos; operator if (a &gt; b &amp;&amp; a != 0) { printf (&apos; The AND (&amp;&amp;) operator said: Both conditions are true. 
 &apos;); } // use logical &apos;OR&apos; and logical &apos;NOT&apos; operator if (n1 &gt; n2 || n2 != 15) if ( ! (a &gt; b &amp;&amp; a != 0 )) { printf (&apos; The NOT (!) operator: Here both conditions are true. 
 &apos;); } else { printf (&apos; The NOT (!) operator: Here, both conditions are true. &apos; &apos; But, the status of the condition is reversed as false. 
&apos;); } return 0; } 

Producción:

 The AND (&amp;&amp;) 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.