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#include <bits/stdc++.h>

using namespace std;

const int N = 50,M = 1200000;
typedef long long ll;


ll x[M],y[M];
ll b[M],c[M],S,mx,mn,ans1,ans2;
int T,n,a[N],len,m,lg2[M];
int main(){
    lg2[0] = -1;for (int i = 1;i < M;i++) lg2[i]=lg2[i/2]+1;

    while (~scanf("%d",&n)){
        mx = 0;mn = 0x7fffffff;mn = mn*mn;
        S = 0;
        m = n/2;
        for (int i = 1;i <= n;i++) {
            scanf("%d",&a[i]);
            S += a[i];
        }
        b[0] = 0;
        for (int i = 1;i <= m;i++){
            for (int j = 0;j < (1<<i>>1);j++){
                x[j] = b[j];
                y[j] = b[j]+a[i];
            }
            int u = 0,v = 0;
            for (int j = 0;j < (1<<i);j++){
                if (u == (1<<i>>1)) b[j] = y[v++];
                else if (v == (1<<i>>1)) b[j] = x[u++];
                else if (x[u] < y[v]) b[j] = x[u++];
                else b[j] = y[v++];
            }
        }

        c[0] = 0;
        for (int i = 1;i <= n-m;i++){
            for (int j = 0;j < (1<<i>>1);j++){
                x[j] = c[j];
                y[j] = c[j]+a[m+i];
            }
            int u = 0,v = 0;
            for (int j = 0;j < (1<<i);j++){
                if (u == (1<<i>>1)) c[j] = y[v++];
                else if (v == (1<<i>>1)) c[j] = x[u++];
                else if (x[u] < y[v]) c[j] = x[u++];
                else c[j] = y[v++];
            }
        }
        int l = (1<<m)-1 , r = (1 << n-m)-1;
        for (int u = 0,v = r;u <= l;u++){
            
            while (v >= 0 && b[u]+c[v] > S/2){
                mn = min(mn,b[u]+c[v]);
                v--;
            }
            if (b[u]+c[v] <= S/2) mx = max(mx,b[u]+c[v]);
            if (v < r) v++;
        }
        if (mx*(S-mx) > mn*(S-mn)) ans1 = mx;
        else ans1 = mn;
        mx = 0;mn = 0x7fffffff;mn = mn*mn;
        for (int u = 0,v = r;u <= l;u++){
            
            while (v >= 0 && (b[u]+c[v])*2 > S/2){
                mn = min(mn,(b[u]+c[v])*2);
                v--;
            }
            if ((b[u]+c[v])*2 <= S/2) mx = max(mx,(b[u]+c[v])*2);
            if (v < r) v++;
        }
        if (mx*(S-mx) >= mn*(S-mn)) ans2 = mx;
        else ans2 = mn;
        ll s1 = ans1*(S-ans1),s2 = ans2*(S-ans2);
        if (s1 == s2) printf("%lld
",max(ans1,S-ans2));
        else if (s1 < s2) printf("%lld
",S-ans2);
        else printf("%lld
",ans1);        
    }
    return 0;
}