#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; typedef long long ll; typedef unsigned long long ull; typedef long double ld; typedef pair P; typedef tuple T; typedef vector vec; inline bool cheak(ll x, ll y, ll xMax, ll yMax){ return x >= 0 && y >= 0 && xMax > x && yMax > y; } inline ll toInt(string s) { ll v; istringstream sin(s); sin >> v; return v; } template inline string toString(T x) { ostringstream sout; sout << x; return sout.str(); } template inline T sqr(T x) { return x*x; } #define For(i,a,b) for(ll (i) = (a);i < (b);(i)++) #define rep(i,n) For(i,0,n) #define rFor(i,a,b) for(ll (i) = (a-1);i >= (b);(i)--) #define rrep(i,n) rFor(i,n,0) #define clr(a) memset((a), 0 ,sizeof(a)) #define mclr(a) memset((a), -1 ,sizeof(a)) #define all(a) (a).begin(),(a).end() #define sz(a) (sizeof(a)) const ll mod = 1e9 + 7; const ll INF = 1e9 + 9; int main() { int n; cin >> n; vector v(n); rep(i, n){ cin >> v[i]; } sort(all(v)); ld ans; if (v.size() % 2){ ans = v[v.size() / 2 ]; } else{ ans = (v[v.size() / 2 - 1] + v[v.size() / 2 ]) / 2; } cout << fixed << setprecision(30) << ans << endl; return 0; }