C++ Exercises: Calculate the sum of all even and odd numbers in an array

Last update on August 11 2025 12:57:14 (UTC/GMT +8 hours)

Sum of Even and Odd Numbers

Write a C++ program to calculate the sum of all even and odd numbers in an array.

Sample Solution:

C++ Code :

#include <iostream> // Including the input-output stream header file

using namespace std; // Using the standard namespace

// Function to separate even and odd numbers and return their sums
int* test(int arr[], int s1) {
    static int result[2]; // Static array to store the sum of even and odd numbers
    for(int i = 0; i <= s1; i++) // Loop through the array elements
    {
        // Checking if the current number in the array is even or odd, and updating the sums accordingly
        arr[i] % 2 == 0 ? result[0] += arr[i] : result[1] += arr[i];
    }
    return result; // Returning the array with sums of even and odd numbers
}

int main() // Start of the main function
{
    int array1[] = {1, 2, 3, 4, 5, 6, 7, 8}; // Initializing an array
    int *eo; // Pointer to hold the result array
    int s1 = sizeof(array1) / sizeof(array1[0]); // Calculating the size of the array

    // Outputting the original array elements
    cout << "Original array: ";
    for (int i = 0; i < s1; i++)
        cout << array1[i] << " ";

    eo = test(array1, s1); // Calling the function to get sums of even and odd numbers

    // Outputting the sum of all even and odd numbers
    cout << "\nSum of all even and odd numbers: " << *(eo + 0) << "," << *(eo + 1);

    return 0; // Return statement indicating successful completion of the program
}

Sample Output:

Original array: 1 2 3 4 5 6 7 8 
Sum of all even and odd numbers: 20,16

Flowchart:

For more Practice: Solve these Related Problems:

Write a C++ program to compute the sum of even and odd numbers in an array and then print both totals in a formatted manner.
Write a C++ program that segregates even and odd numbers from an array, calculates their sums, and displays the results side by side.
Write a C++ program to read an array of integers, sum the even and odd numbers separately, and then output the difference between the sums.
Write a C++ program that computes the sum of even and odd numbers in a dynamically allocated array and prints the results with labels.

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C++ Code Editor:

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