結果

問題 No.1031 いたずら好きなお姉ちゃん
ユーザー kcvlex
提出日時 2020-04-19 00:19:17
言語 C++17
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 484 ms / 3,500 ms
コード長 4,196 bytes
コンパイル時間 1,721 ms
コンパイル使用メモリ 150,216 KB
最終ジャッジ日時 2025-01-09 21:20:53
ジャッジサーバーID
(参考情報)
judge5 / judge1
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 3
other AC * 53
権限があれば一括ダウンロードができます

ソースコード

diff #

#include <limits>
#include <initializer_list>
#include <utility>
#include <bitset>
#include <tuple>
#include <type_traits>
#include <functional>
#include <string>
#include <array>
#include <deque>
#include <list>
#include <queue>
#include <stack>
#include <vector>
#include <map>
#include <set>
#include <unordered_map>
#include <unordered_set>
#include <iterator>
#include <algorithm>
#include <complex>
#include <random>
#include <numeric>
#include <iostream>
#include <iomanip>
#include <sstream>
#include <regex>
#include <cassert>
#include <cstddef>
#define endl codeforces
#define ALL(v) std::begin(v), std::end(v)
#define ALLR(v) std::rbegin(v), std::rend(v)
using ll = std::int64_t;
using ull = std::uint64_t;
using pii = std::pair<int, int>;
using tii = std::tuple<int, int, int>;
using pll = std::pair<ll, ll>;
using tll = std::tuple<ll, ll, ll>;
template <typename T> using vec = std::vector<T>;
template <typename T> using vvec = vec<vec<T>>;
template <typename T> const T& var_min(const T &t) { return t; }
template <typename T> const T& var_max(const T &t) { return t; }
template <typename T, typename... Tail> const T& var_min(const T &t, const Tail&... tail) { return std::min(t, var_min(tail...)); }
template <typename T, typename... Tail> const T& var_max(const T &t, const Tail&... tail) { return std::max(t, var_max(tail...)); }
template <typename T, typename... Tail> void chmin(T &t, const Tail&... tail) { t = var_min(t, tail...); }
template <typename T, typename... Tail> void chmax(T &t, const Tail&... tail) { t = var_max(t, tail...); }
template <typename T> const T& clamp(const T &t, const T &low, const T &high) { return std::max(low, std::min(high, t)); }
template <typename T> void chclamp(T &t, const T &low, const T &high) { return t = clamp(t, low, high); }
template <typename T> T make_v(T init) { return init; }
template <typename T, typename... Tail> auto make_v(T init, std::size_t s, Tail... tail) { auto v = std::move(make_v(init, tail...)); return vec<decltype(v)>(s, v); }
template <typename T, std::size_t Head, std::size_t ...Tail> struct multi_dem_array { using type = std::array<typename multi_dem_array<T, Tail...>::type, Head>; };
template <typename T, std::size_t Head> struct multi_dem_array<T, Head> { using type = std::array<T, Head>; };
template <typename T, std::size_t ...Args> using mdarray = typename multi_dem_array<T, Args...>::type;
namespace init__ { struct InitIO { InitIO() { std::cin.tie(nullptr); std::ios_base::sync_with_stdio(false); std::cout << std::fixed << std::setprecision(30); } } init_io; }

const ll inf = 5e15;

vec<ll> cnt_l(vec<ll> p) {
    ll n = p.size();
    p.push_back(n);
    vec<ll> rp(n + 1);
    for (ll i = 0; i < n; i++) rp[p[i]] = i;

    auto adjust = [&] {
        std::set<ll> unused;
        vec<ll> ret(n + 1, n);
        for (ll i = 0; i <= n; i++) unused.insert(i);
        for (ll e = n - 1; 0 <= e; e--) {
            ll pos = rp[e];
            unused.erase(pos);
            auto ite = unused.lower_bound(pos);
            ret[e] = *ite;
        }
        return ret;
    }();

    auto dub = make_v<ll>(0, 20, n + 1);
    for (ll i = 0; i <= n; i++) dub[0][i] = adjust[i];
    for (ll i = 0; i + 1 < 20; i++) for (ll j = 0; j <= n; j++) {
        ll pos = dub[i][j];
        ll val = p[pos];
        dub[i + 1][j] = dub[i][val];
    }


    auto get_cnt = [&](ll pos, ll r) {
        ll ret = 0;
        for (ll i = 19; 0 <= i; i--) {
            ll mask = 1ll << i;
            ll nxt = dub[i][p[pos]];
            if (r <= nxt) continue;
            ret += mask;
            pos = nxt;
        }
        return ret;
    };
   
    vec<ll> ret(n);
    std::set<ll> used;
    used.insert(n);

    for (ll e = n - 1; 0 <= e; e--) {
        ll pos = rp[e];
        ll r = *used.lower_bound(pos);
        ret[e] = get_cnt(pos, r);
        used.insert(pos);
    }
    return ret;
}

int main() {
    ll n;
    std::cin >> n;
    vec<ll> p(n);
    for (ll &e : p) {
        std::cin >> e;
        e--;
    }

    auto lv = cnt_l(p);
    std::reverse(ALL(p));
    auto rv = cnt_l(p);
    ll ans = 0;
    for (ll i = 0; i < n; i++) ans += lv[i] + rv[i];
    std::cout << ans << '\n';
    return 0;
}
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