#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; #define REP(i,a,n) for(int i=(a); i<(int)(n); i++) #define rep(i,n) REP(i,0,n) #define FOR(it,c) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it) #define ALLOF(c) (c).begin(), (c).end() typedef long long ll; int main(){ int N; cin >> N; vector v; rep(i,N){ int a; cin >> a; v.push_back(a); } sort(ALLOF(v)); if(N%2==0){ cout << (v[N/2-1]+v[N/2])/2.0 << endl; }else{ cout << v[N/2] << endl; } return 0; }