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#include <stdio.h>

#define MAX 1010

int tab[MAX];

int main()
{
    int n, a;
    scanf("%d", &n);

    while (n--)
    {
        scanf("%d", &a);
        tab[a]++;
    }

    int answer = 0;
    int left = 0;
    for (int i = MAX - 1; i >= 0; --i)
    {
        if (i % 2 == 0)
        {
            answer += tab[i] * i;
        }
        else if (tab[i])
        {
            if (left > 0)
            {
                tab[i]--;

                answer += i + left;
                left = 0;
            }

            answer += (tab[i] - tab[i] % 2) * i;

            if (tab[i] % 2 == 1)
            {
                left = i;
            }
        }
    }

    if (answer > 0)
        printf("%d\n", answer);
    else
        printf("NIESTETY\n");

    return 0;
}