#include<bits/stdc++.h>
#define ll long long

using namespace std;

void solve()
{
    int maxn[2] = {0};
    int n; cin >> n;
    while (n--) {
        int x; cin >> x;
        if (x > maxn[0])maxn[1] = maxn[0], maxn[0] = x;
        else if (x > maxn[1])maxn[1] = x;
    }
    cout<<maxn[0]+maxn[1];
}

int main()
{
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    int t = 1;
    while (t--)solve();
    return 0;
}