#include using namespace std; #define rep(i, n) for (int i = 0; i < (n); i++) typedef long long ll; typedef pair pii; typedef vector vll; typedef vector vi; typedef vector> vvi; typedef vector> vvll; const ll inf = 1e16; const ll md = 1000000007; int main() { int n; cin>>n; vi a(n); rep(i,n) cin>>a[i]; sort(a.begin(),a.end()); if(n&1) cout<