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Logical Operators in C++

In the C++ programming language, logical operators are applied to group or reverse multiple user-defined program expressions or conditions. Logical operators output a Boolean result (either true or false) based on the simultaneous evaluation of multiple program condition implementations. Logical operators in C++ are commonly used to create complex conditions or logical expressions in conditional program statements and loops.

Details About Logical Operators

So, let’s get to know logical operator expressions in C++ programming better.

Logical AND (&&) Operator in C++.

In a C++ program, the logical AND operator && is used to check or analyze whether both user-defined custom conditions or expressions in the current program are true or false. Remember, the AND C++ logical operator outputs a true result only when the condition is true. When both user-defined && operand expressions are true, it returns false.

Syntax of the Logical AND (&&) Operator.

condition1 && condition2

Example of the logical AND (&&) operator.

#include <iostream>

using namespace std;

int main() {

int p = 3, q ​​= 7;

if (p > 1 && q > 4) {

cout << “Here Both p && q condition expression is true.” << endl; // Result is – Here Both p && q condition expression is true

}

if (p > 7 && q < 1) {

cout << “Here Both p && q condition expression is false.” << endl;

}

return 0;

}

logical AND (&&) operator explanation.

• Here, in the AND logical operator, the first if statement has p > 1 as true, and q > 4 as a true expression or condition. Therefore, p && q are treated as true, and a user-defined console message is printed.
• Similarly, in the second if statement, p > 7 && q < 1 is false. Therefore, the logical AND (&&) results in a false output, and no user-defined console message is printed.

Logical OR (||) Operator in C++.

In a C++ program, the logical OR operator || checks and analyzes whether at least one of the user-defined expressions or conditions in the current program is true. If any one of the operand conditions in the AND logical operator is declared true, it returns a true output value. If both the user-defined declaration and logical operator conditions are false, it returns a false output value. So it returns a false output value result.

Syntax of the Logical OR (||) Operator.

condition1 || condition2

Example of the Logical OR (||) Operator.

#include <iostream>

using namespace std;

int main() {

int p = 4, q = -8;

if (p > 3 || q > 2) {

cout << “Here at least one of the p || q expression condition must be true.” <<endl; // Result is – Here At least one of the p || q expression condition must be true

}

if (p < 2 || q < -4) {

cout << “Here p || q expression statement result is.” <<endl;

}

return 0;

}

Logical OR (||) Operator explanation.

• Here, in the AND logical operator, the first if statement outputs p > 3 as true, making the p || q condition true, and printing a message to the user-defined console screen.
• Similarly, in the second if statement, both user-defined conditions are false. Consequently, the logical OR (||) results in false, and no message is printed to the user-defined console screen.

Logical NOT (!) Operator in C++.

In a C++ program, the logical NOT operator is used to reverse the boolean value of a user-defined logical expression in the !NOT condition. If the user-defined logical NOT condition expression is true, the !NOT operator reverses it to false.

Syntax of the Logical NOT (!) Operator.

!condition

Example of the Logical NOT (!) Operator.

#include <iostream>

using namespace std;

#include <iostream>

using namespace std;

int main() {

bool isTest = false;

if (!isTest) {

cout << “You have no medical permit.” << endl; // Result is – You have no medical permit.

}

isTest = true;

if (!isTest) {

cout << “You have no medical permit.” << endl;

}

return 0;

}

Logical NOT (!) Operator explanation.

• Here, in the AND logical operator, the condition !isTest is defined as true. Because isTest was previously defined as false, the first message is printed on the console.
• When isTest is defined or set to true, !isTest becomes false, and the second message is not printed on the console.

Grouping multiple logical operators in C++.

C++ users can use multiple logical operators together to create more than one complex logical expression condition in a program.

Example of multiple logical operators.

#include <iostream>

using namespace std;

int main() {

int p = 7, q = 3, r = 2;

if (p > q && (q > r || r == 2)) {

cout << “Here all user-defined all logical expression condition is true.” << endl; // Result is – Here all user-defined all logical expression condition is true

}

return 0;

}

Explanation of multiple logical operators.

• Here the evolution of (p > q && (q > r || r == 2)) into a user-defined logical expression is done like this. For example,
• p > q is defined as true (because 7 > 3).
• The second internal condition analyzes q > r || r == 2. The expression q > r is true (because 3 > 2), so logical OR (||) outputs true.
• For this reason, the user-defined complete condition is defined as true, and a user-defined message is printed on the console screen according to the output.

Explanation of Logical Operators

AND (&&), OR (||), NOT (!), logical operators summary in C++.

• Logical operators in C++ programs help group multiple user-defined custom condition expressions or reverse the Boolean value of a condition.
• The AND (&&) logical operator requires both user-defined conditions to be true for the condition result to be true.
• The OR (||) logical operator requires at least one user-defined condition expression to be true for the condition result to be true.
• The NOT (!) logical operator reverses the truth boolean value of the condition.
• The use of logical operators in C++ programs helps control large-scale decision-making, program loops, and the default program flow behavior.