The provided C++ code is designed to count the number of even and odd numbers entered by the user, excluding the terminating 0.

## Code

```
/*
* Program to count even and odd numbers.
*
* This program prompts the user to enter a sequence of integers, ending the sequence with a 0.
* It then counts the number of even and odd numbers entered (excluding the final 0) and displays the counts.
*
* How it works:
* 1. The program initializes two counters for even and odd numbers.
* 2. It prompts the user to enter a number and reads the user input.
* 3. If the number is not 0, it checks if the number is even or odd and increments the respective counter.
* 4. The program repeats steps 2 and 3 until the user enters 0.
* 5. Finally, it displays the counts of even and odd numbers.
*
* Note: The program considers 0 as neither even nor odd for the purpose of this count.
*/
#include <iostream>
using namespace std;
int main() {
int evenCount = 0; // Counter for even numbers
int oddCount = 0; // Counter for odd numbers
int userInput; // Variable to store the user's input
cout << "Enter a number: ";
cin >> userInput;
while (userInput != 0) {
if (userInput % 2 == 1)
oddCount++; // Increment odd counter if the number is odd
else
evenCount++; // Increment even counter if the number is even
cout << "Enter a number: ";
cin >> userInput;
}
cout << "Even numbers : " << evenCount << endl; // Display the count of even numbers
cout << "Odd numbers : " << oddCount << endl; // Display the count of odd numbers
return 0;
}
```

## Explanation

The provided C++ code is designed to count the number of even and odd numbers entered by the user, excluding the terminating 0. The program operates in a loop, prompting the user to input integers until a 0 is entered, which signals the end of input. It utilizes the modulo operator (`%`

) to distinguish between even and odd numbers.

Initially, the program declares and initializes two integer variables, `evenCount`

and `oddCount`

, to zero. These variables serve as counters for the even and odd numbers, respectively.

```
int evenCount = 0; // Counter for even numbers
int oddCount = 0; // Counter for odd numbers
```

The program then enters a loop, first prompting the user to enter a number. This is achieved using `cout`

for the prompt and `cin`

to read the user’s input into the variable `userInput`

.

```
cout << "Enter a number: ";
cin >> userInput;
```

Within the loop, the program checks if the input is not 0. If it’s not, it determines whether the number is even or odd by using the modulo operation (`userInput % 2`

). If the result is 1, the number is odd, and `oddCount`

is incremented. Otherwise, the number is even, and `evenCount`

is incremented.

```
if (userInput % 2 == 1)
oddCount++; // Increment odd counter if the number is odd
else
evenCount++; // Increment even counter if the number is even
```

This process repeats until the user inputs 0, at which point the loop terminates. Finally, the program outputs the counts of even and odd numbers using `cout`

.

```
cout << "Even numbers : " << evenCount << endl;
cout << "Odd numbers : " << oddCount << endl;
```

This code snippet effectively demonstrates basic C++ input/output operations, conditional statements, and loop control structures, making it a straightforward example for developers familiar with C++ but new to this specific logic.

## Output

```
Enter a number: 13
Enter a number: 212
Enter a number: 345
Enter a number: 23
Enter a number: 0
Even numbers : 1
Odd numbers : 3
Process finished with exit code 0
```