01. Below Average Only

#include <iostream>
#include <vector>

using namespace std;

int main() {
    int arrLen, sumNumbers = 0, averageNum, oddSum = 0, evenSum = 0;
    cin >> arrLen;

    int* numbers = new int[arrLen];

    for (int i = 0; i < arrLen; i++) {
        cin >> numbers[i];
        sumNumbers += numbers[i];
    }

    averageNum = (double)sumNumbers / arrLen;

    for (int i = 0; i < arrLen; i++) {
        if (numbers[i] <= averageNum) {
            (i % 2 == 1 ? oddSum : evenSum) += numbers[i];
        }
    }

    cout << oddSum * evenSum << endl;
    return 0;
}