comparison operator

Comparison operators in C++ compare two values or variables. The result of a comparison is a boolean value: true if the comparison is correct and false otherwise. These operators are essential in controlling the flow of a program, particularly in decision-making constructs like if, else, while, and for loops.

Types of Comparison Operators

C++ supports the following comparison operators:

Equal to (==)

• Description: Checks if the value of two operands are equal.
• Example: a == b returns true if a is equal to b, otherwise it returns false.

Not equal to (!=)

• Description: Checks if the value of two operands is not equal.
• Example: a != b returns true if a is not equal to b, otherwise it returns false.

More significant than (>)

• Description: Checks if the value of the left operand is greater than that of the right operand.
• Example: a > b returns true if a is greater than b, otherwise it returns false.

Less than (<)

• Description: Checks if the value of the left operand is less than the value of the right operand.
• Example: a < b returns true if a is less than b, otherwise it returns false.

Greater than or equal to (>=)

• Description: Checks if the value of the left operand is greater than or equal to the value of the right operand.
• Example: a >= b returns true if a is greater than or equal to b, otherwise it returns false.

Less than or equal to (<=)

• Description: Checks if the value of the left operand is less than or equal to the value of the right operand.
• Example: a <= b returns true if a is less than or equal to b otherwise it returns false.

Example Code

Here is an example that demonstrates how to use comparison operators in C++:

#include <iostream>
using namespace std;
int main() {
   int a = 10, b = 20;
   // Equal to
   if (a == b) {
       cout << a << " is equal to " << b << endl;
   } else {
       cout << a << " is not equal to " << b << endl;
   }
   // Not equal to
   if (a != b) {
       cout << a << " is not equal to " << b << endl;
   }
   // Greater than
   if (a > b) {
       cout << a << " is greater than " << b << endl;
   } else {
       cout << a << " is not greater than " << b << endl;
   }
   // Less than
   if (a < b) {
       cout << a << " is less than " << b << endl;
   } else {
       cout << a << " is not less than " << b << endl;
   }
   // Greater than or equal to
   if (a >= b) {
       cout << a << " is greater than or equal to " << b << endl;
   } else {
       cout << a << " is not greater than or equal to " << b << endl;
   }
   // Less than or equal to
   if (a <= b) {
       cout << a << " is less than or equal to " << b << endl;
   } else {
       cout << a << " is not less than or equal to " << b << endl;
   }
   return 0;
}

Explanation of the Example

1. Equal to (a == b): Compares if a is equal to b. In this case, it will return false since 10 is not equal to 20.
2. Not equal to (a != b): Compares if a is not equal to b. This will return true since 10 is not equal to 20.
3. Greater than (a > b): Compares if a is greater than b. This will return false because 10 is not greater than 20.
4. Less than (a < b): Compares if a is less than b. This will return true because 10 is less than 20.
5. Greater than or equal to (a >= b): Compares if a is greater than or equal to b. This will return false because 10 is neither greater than nor equal to 20.
6. Less than or equal to (a <= b): Compares if a is less than or equal to b. This will return true because 10 is less than 20.

The code demonstrates how these comparison operators can be used in conjunction with control statements like if-else to make decisions based on the results of the comparisons.

Conclusion

Comparison operators are essential for controlling the flow of a C++ program. They allow you to compare values and make decisions based on those comparisons. Understanding these operators and practicing their use in conditional statements will greatly enhance your ability to write logical and effective C++ programs.