#line 1 "a.cpp" #define PROBLEM "https://yukicoder.me/problems/no/2126" #line 2 "/home/kuhaku/atcoder/github/algo/lib/template/template.hpp" #pragma GCC target("sse4.2,avx2,bmi2") #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #include template bool chmax(T &a, const U &b) { return a < (T)b ? a = (T)b, true : false; } template bool chmin(T &a, const U &b) { return (T)b < a ? a = (T)b, true : false; } constexpr std::int64_t INF = 1000000000000000003; constexpr int Inf = 1000000003; constexpr int MOD = 1000000007; constexpr int MOD_N = 998244353; constexpr double EPS = 1e-7; constexpr double PI = M_PI; #line 3 "/home/kuhaku/atcoder/github/algo/lib/template/macro.hpp" #define FOR(i, m, n) for (int i = (m); i < int(n); ++i) #define FORR(i, m, n) for (int i = (m)-1; i >= int(n); --i) #define FORL(i, m, n) for (int64_t i = (m); i < int64_t(n); ++i) #define rep(i, n) FOR (i, 0, n) #define repn(i, n) FOR (i, 1, n + 1) #define repr(i, n) FORR (i, n, 0) #define repnr(i, n) FORR (i, n + 1, 1) #define all(s) (s).begin(), (s).end() #line 3 "/home/kuhaku/atcoder/github/algo/lib/template/sonic.hpp" struct Sonic { Sonic() { std::ios::sync_with_stdio(false); std::cin.tie(nullptr); } constexpr void operator()() const {} } sonic; #line 5 "/home/kuhaku/atcoder/github/algo/lib/template/atcoder.hpp" using namespace std; using ll = std::int64_t; using ld = long double; template std::istream &operator>>(std::istream &is, std::pair &p) { return is >> p.first >> p.second; } template std::istream &operator>>(std::istream &is, std::vector &v) { for (T &i : v) is >> i; return is; } template std::ostream &operator<<(std::ostream &os, const std::pair &p) { return os << '(' << p.first << ',' << p.second << ')'; } template std::ostream &operator<<(std::ostream &os, const std::vector &v) { for (auto it = v.begin(); it != v.end(); ++it) { os << (it == v.begin() ? "" : " ") << *it; } return os; } template void co(Head &&head, Tail &&...tail) { if constexpr (sizeof...(tail) == 0) std::cout << head << '\n'; else std::cout << head << ' ', co(std::forward(tail)...); } template void ce(Head &&head, Tail &&...tail) { if constexpr (sizeof...(tail) == 0) std::cerr << head << '\n'; else std::cerr << head << ' ', ce(std::forward(tail)...); } template auto make_vector(T x, int arg, Args... args) { if constexpr (sizeof...(args) == 0) return std::vector(arg, x); else return std::vector(arg, make_vector(x, args...)); } void setp(int n) { std::cout << std::fixed << std::setprecision(n); } void Yes(bool is_correct = true) { std::cout << (is_correct ? "Yes" : "No") << '\n'; } void No(bool is_not_correct = true) { Yes(!is_not_correct); } void YES(bool is_correct = true) { std::cout << (is_correct ? "YES" : "NO") << '\n'; } void NO(bool is_not_correct = true) { YES(!is_not_correct); } void Takahashi(bool is_correct = true) { std::cout << (is_correct ? "Takahashi" : "Aoki") << '\n'; } void Aoki(bool is_not_correct = true) { Takahashi(!is_not_correct); } #line 3 "a.cpp" int main(void) { int n; cin >> n; vector a(n); cin >> a; int m = *max_element(all(a)); vector c(100002); for (auto x : a) ++c[x]; --c[m]; rep (i, 100002) { if (c[i] == 2) continue; if (c[i] >= 3 && m != -1) { ++c[m]; m = i; continue; } else if (c[i] == 1) { if (m != -1 && m != i) { m = -1; } else { co(i); return 0; } } co(i); return 0; } return 0; }