Integers that are perfectly divisible by 2 are called even numbers.

And those integers that are not perfectly divisible by 2 are not known as odd numbers.

To check whether an integer is even or odd, the remainder is calculated when it is divided by 2 using modulus operator **%**. If the remainder is zero, that integer is even if not that integer is odd.

## Example 1: Check Whether Number is Even or Odd using if else

```
#include <iostream>
using namespace std;
int main() {
int n;
cout << "Enter an integer: ";
cin >> n;
if ( n % 2 == 0)
cout << n << " is even.";
else
cout << n << " is odd.";
return 0;
}
```

**Output**

Enter an integer: 23 23 is odd.

In this program, an `if..else`

statement is used to check whether `n % 2 == 0`

is `true`

or not.

If this expression is `true`

, `n` is even. Else, `n` is odd.

You can also use ternary operators `?:`

instead of `if..else`

statement. The ternary operator is a shorthand notation of `if...else`

statement.

## Example 2: Check Whether Number is Even or Odd using ternary operators

```
#include <iostream>
using namespace std;
int main() {
int n;
cout << "Enter an integer: ";
cin >> n;
(n % 2 == 0) ? cout << n << " is even." : cout << n << " is odd.";
return 0;
}
```