#include #define REP_(i, a_, b_, a, b, ...) \ for (int i = (a), _Z_##i = (b); i < _Z_##i; ++i) #define REP(i, ...) REP_(i, __VA_ARGS__, __VA_ARGS__, 0, __VA_ARGS__) #define ALL(x) std::begin(x), std::end(x) using i64 = long long; using u64 = unsigned long long; template inline bool chmax(T &a, U b) { return a < b and ((a = std::move(b)), true); } template inline bool chmin(T &a, U b) { return a > b and ((a = std::move(b)), true); } template inline int ssize(const T &a) { return (int)std::size(a); } template std::istream &operator>>(std::istream &is, std::vector &a) { for (auto &x : a) is >> x; return is; } template std::ostream &print_seq(const Container &a, std::string_view sep = " ", std::string_view ends = "\n", std::ostream &os = std::cout) { auto b = std::begin(a), e = std::end(a); for (auto it = std::begin(a); it != e; ++it) { if (it != b) os << sep; os << *it; } return os << ends; } template struct is_iterable : std::false_type {}; template struct is_iterable())), decltype(std::end(std::declval()))>> : std::true_type {}; template ::value && !std::is_same::value && !std::is_same::value>> std::ostream &operator<<(std::ostream &os, const T &a) { return print_seq(a, ", ", "", (os << "{")) << "}"; } template std::ostream &operator<<(std::ostream &os, const std::pair &a) { return os << "(" << a.first << ", " << a.second << ")"; } #ifdef ENABLE_DEBUG template void pdebug(const T &value) { std::cerr << value; } template void pdebug(const T &value, const Ts &...args) { pdebug(value); std::cerr << ", "; pdebug(args...); } #define DEBUG(...) \ do { \ std::cerr << " \033[33m (L" << __LINE__ << ") "; \ std::cerr << #__VA_ARGS__ << ":\033[0m "; \ pdebug(__VA_ARGS__); \ std::cerr << std::endl; \ } while (0) #else #define pdebug(...) #define DEBUG(...) #endif using namespace std; i64 solve() { int n; cin >> n; vector a(n); cin >> a; set> s; REP(i, n) { s.emplace(a[i], i); } vector b; deque blocked(n, false); for (auto [x, i] : s) { if (blocked[i]) continue; b.push_back(x); blocked[i] = true; if (i > 0) blocked[i - 1] = true; } DEBUG(b); return ssize(b); } int main() { ios_base::sync_with_stdio(false), cin.tie(nullptr); cout << solve() << "\n"; }