#include <iostream>

void quickSort(int* array, int low, int high)
{
    int i = low;
    int j = high;
    int pivot = array[(i + j) / 2];
    int temp;

    while (i <= j) {
        while (array[i] < pivot)
            i++;
        while (array[j] > pivot)
            j--;
        if (i <= j) {
            temp = array[i];
            array[i] = array[j];
            array[j] = temp;
            i++;
            j--;
        }
    }
    if (j > low)
        quickSort(array, low, j);
    if (i < high)
        quickSort(array, i, high);
}

int main()
{
    int n, R, L, max_sum, min_sum, curr_sum;
    std::cin >> n;
    int a[n];

    for (int i = 0; i < n; i++)
        std::cin >> a[i];

    quickSort(a, 0, n);

    R = 0;
    max_sum = a[0];
    curr_sum = a[0];

    for (L = 0; L < n; L++) {

        if (L >= (n - 2)) {
            min_sum = a[L];
        }
        else
            min_sum = a[L] + a[L + 1];

        while ((R < (n - 1)) && (a[R + 1] <= min_sum)) {
            R += 1;
            curr_sum += a[R];
        }

        if (curr_sum > max_sum)
            max_sum = curr_sum;

        curr_sum -= a[L];
    }

    std::cout << max_sum;

    return 0;
}