# Relational and logical operators

Relational operators are used to compare values with each other. They return a logical result: `true` or `false`. Values that are linked with relational operators are called elementary statements in propositional logic.
A typical example of a Boolean logical operator is the `and` operation: It always returns `true` if all operands are also `true`.

## Code Example

``````#include &lt;iostream&gt;
using namespace std;

int main() {
int a = 0, i = 20, b = 8;
while (a != b && i >= a+b) {
cout << a << " is equal " << b << endl;
a++;
}
cout << a << " is unequal " << b << endl;
}``````
##### Output
``````0 is equal 8
1 is equal 8
2 is equal 8
3 is equal 8
4 is equal 8
5 is equal 8
6 is equal 8
7 is equal 8
8 is unequal 8``````

### Code Explanation

1. The code includes the `iostream` library, which provides input and output functionality in C++.
2. The line `using namespace std;` declares that we’re using the `std` namespace, which contains various standard C++ functions and objects, including `cout`.
3. The `int main()` function is the entry point of the program. It returns an integer value, typically `0`, indicating successful execution.
4. Inside the `main()` function, three variables are declared and initialized:
• `a` is an `int` variable initialized with the value `0`.
• `i` is an `int` variable initialized with the value `20`.
• `b` is an `int` variable initialized with the value `8`.
5. The `while` loop is used to execute a block of code repeatedly as long as a certain condition is true.
6. The condition `(a != b && i >= a+b)` is checked before each iteration of the loop. The loop will continue as long as `a` is not equal to `b` and the value of `i` is greater than or equal to the sum of `a` and `b`.
7. If the condition is true, the code block inside the loop is executed. The code outputs the string `a is equal b`, where `a` and `b` are the values of the variables, and then increments the value of `a` by 1 using the `a++` statement.
8. Once the condition `(a != b && i >= a+b)` becomes false, the loop terminates, and the program continues with the next line of code.
9. The line `cout << a << " is unequal " << b << endl;` outputs the string `a is unequal b`, where `a` and `b` are the final values of the variables after the loop.