Submission #844848

#	Time	Username	Problem	Language	Result	Execution time	Memory
844848		hamerin	Salesman (IOI09_salesman)	C++17	100 / 100	802 ms	56388 KiB

salesman

#include <bits/stdc++.h>

#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")

using namespace std;

using li = long long;
using ld = long double;
using pi = pair<int, int>;
using pli = pair<li, li>;

#define all(c) c.begin(), c.end()
#define prec(n) setprecision(n) << fixed

/////////////////////////////////////////////////////////////////////////////////////////////
/*
 * Author : jinhan814
 * Date : 2021-05-06
 * Source : https://blog.naver.com/jinhan814/222266396476
 * Description : FastIO implementation for cin, cout.
 */
constexpr int SZ = 1 << 20;

class INPUT {
private:
    char read_buf[SZ];
    int read_idx, next_idx;
    bool __END_FLAG__, __GETLINE_FLAG__;
public:
    explicit operator bool() { return !__END_FLAG__; }
    bool IsBlank(char c) { return c == ' ' || c == '\n'; }
    bool IsEnd(char c) { return c == '\0'; }
    char _ReadChar() {
        if (read_idx == next_idx) {
            next_idx = fread(read_buf, sizeof(char), SZ, stdin);
            if (next_idx == 0) return 0;
            read_idx = 0;
        }
        return read_buf[read_idx++];
    }
    char ReadChar() {
        char ret = _ReadChar();
        for (; IsBlank(ret); ret = _ReadChar());
        return ret;
    }
    template<typename T> T ReadInt() {
        T ret = 0; char cur = _ReadChar(); bool flag = 0;
        for (; IsBlank(cur); cur = _ReadChar());
        if (cur == '-') flag = 1, cur = _ReadChar();
        for (; !IsBlank(cur) && !IsEnd(cur); cur = _ReadChar()) ret = 10 * ret + (cur & 15);
        if (IsEnd(cur)) __END_FLAG__ = 1;
        return flag ? -ret : ret;
    }
    string ReadString() {
        string ret; char cur = _ReadChar();
        for (; IsBlank(cur); cur = _ReadChar());
        for (; !IsBlank(cur) && !IsEnd(cur); cur = _ReadChar()) ret.push_back(cur);
        if (IsEnd(cur)) __END_FLAG__ = 1;
        return ret;
    }
    double ReadDouble() {
        string ret = ReadString();
        return stod(ret);
    }
    string getline() {
        string ret; char cur = _ReadChar();
        for (; cur != '\n' && !IsEnd(cur); cur = _ReadChar()) ret.push_back(cur);
        if (__GETLINE_FLAG__) __END_FLAG__ = 1;
        if (IsEnd(cur)) __GETLINE_FLAG__ = 1;
        return ret;
    }
    friend INPUT& getline(INPUT& in, string& s) { s = in.getline(); return in; }
} _in;

class OUTPUT {
private:
    char write_buf[SZ];
    int write_idx;
public:
    ~OUTPUT() { Flush(); }
    explicit operator bool() { return 1; }
    void Flush() {
        fwrite(write_buf, sizeof(char), write_idx, stdout);
        write_idx = 0;
    }
    void WriteChar(char c) {
        if (write_idx == SZ) Flush();
        write_buf[write_idx++] = c;
    }
    template<typename T> int GetSize(T n) {
        int ret = 1;
        for (n = n >= 0 ? n : -n; n >= 10; n /= 10) ret++;
        return ret;
    }
    template<typename T> void WriteInt(T n) {
        int sz = GetSize(n);
        if (write_idx + sz >= SZ) Flush();
        if (n < 0) write_buf[write_idx++] = '-', n = -n;
        for (int i = sz; i-- > 0; n /= 10) write_buf[write_idx + i] = n % 10 | 48;
        write_idx += sz;
    }
    void WriteString(string s) { for (auto& c : s) WriteChar(c); }
    void WriteDouble(double d) { WriteString(to_string(d)); }
} _out;

/* operators */
INPUT& operator>> (INPUT& in, char& i) { i = in.ReadChar(); return in; }
INPUT& operator>> (INPUT& in, string& i) { i = in.ReadString(); return in; }
template<typename T, typename std::enable_if_t<is_arithmetic_v<T>>* = nullptr>
INPUT& operator>> (INPUT& in, T& i) {
    if constexpr (is_floating_point_v<T>) i = in.ReadDouble();
    else if constexpr (is_integral_v<T>) i = in.ReadInt<T>(); return in; }

OUTPUT& operator<< (OUTPUT& out, char i) { out.WriteChar(i); return out; }
OUTPUT& operator<< (OUTPUT& out, string i) { out.WriteString(i); return out; }
template<typename T, typename std::enable_if_t<is_arithmetic_v<T>>* = nullptr>
OUTPUT& operator<< (OUTPUT& out, T i) {
    if constexpr (is_floating_point_v<T>) out.WriteDouble(i);
    else if constexpr (is_integral_v<T>) out.WriteInt<T>(i); return out; }

/* macros */
#define fastio 1
#define cin _in
#define cout _out
#define istream INPUT
#define ostream OUTPUT
/////////////////////////////////////////////////////////////////////////////////////////////


template <typename T>
class SegTree {
   public:
    uint N;
    vector<T> vl;

    explicit SegTree(uint _N) : N(_N), vl(N << 2, numeric_limits<T>::min() / T(2)) {}

    void update(uint s, uint e, uint n, uint t, T x) {
        if (t < s || e < t) return;
        if (s == e) {
            vl[n] = x;
            return;
        }

        uint m = (s + e) >> 1, k = n << 1;
        update(s, m, k, t, x);
        update(m + 1, e, k | 1, t, x);
        vl[n] = max(vl[k], vl[k | 1]);
    }

    T query(uint s, uint e, uint n, uint l, uint r) {
        if (r < s || e < l) return numeric_limits<T>::min() / T(2);
        if (l <= s && e <= r) return vl[n];

        uint m = (s + e) >> 1, k = n << 1;
        return max(query(s, m, k, l, r), query(m + 1, e, k | 1, l, r));
    }

    inline void update(uint t, T x) { update(0, N - 1, 1, t, x); }
    inline T query(uint l, uint r) { return query(0, N - 1, 1, l, r); }
};

int main() {
    ios_base::sync_with_stdio(false);
    // cin.tie(nullptr);
    // cout.tie(nullptr);

    int N, U, D, S;
    cin >> N >> U >> D >> S;

    vector<int> locs(1, S), days({0, 500001});
    vector<tuple<int, int, int>> markets;
    markets.emplace_back(0, S, 0);
    markets.emplace_back(500001, S, 0);
    for (int i = 0; i < N; i++) {
        int T, L, M;
        cin >> T >> L >> M;
        markets.emplace_back(T, L, M);
        locs.emplace_back(L);
        days.emplace_back(T);
    }

    sort(all(days)), days.erase(unique(all(days)), days.end());
    sort(all(locs)), locs.erase(unique(all(locs)), locs.end());

    vector<vector<pi>> marketsByDay(days.size());
    for (auto [T, L, M] : markets)
        marketsByDay[lower_bound(all(days), T) - days.begin()].emplace_back(L, M);
    for (auto& day : marketsByDay) sort(all(day));

    bool init = true;
    vector<int> revenues(locs.size(), numeric_limits<int>::min());
    SegTree<int> upper((uint)locs.size()), lower((uint)locs.size());
    for (const auto& marketsOfDay : marketsByDay) {
        if (init) {
            const int Lc = lower_bound(all(locs), marketsOfDay[0].first) - locs.begin();
            upper.update(Lc, -U * marketsOfDay[0].first);
            lower.update(Lc, D * marketsOfDay[0].first);

            init = false;
            continue;
        }

        vector<int> idxs(marketsOfDay.size());
        vector<int> queryResults(marketsOfDay.size());
        for (int i = 0; i < (int)marketsOfDay.size(); i++) {
            const auto [L, M] = marketsOfDay[i];
            const int Lc = lower_bound(all(locs), L) - locs.begin();

            idxs[i] = Lc;
            queryResults[i] = max(upper.query(Lc, (uint)locs.size() - 1) + U * L,
                                  lower.query(0, Lc) - D * L);
        }

        optional<pi> last = nullopt;
        for (int i = 0; i < (int)marketsOfDay.size(); i++) {
            const auto [L, M] = marketsOfDay[i];
            const int Lc = idxs[i];

            int R = max(queryResults[i],
                        last ? last->first - D * (L - last->second) : numeric_limits<int>::min()) +
                    M;

            revenues[Lc] = max(revenues[Lc], R);
            last = {R, L};
        }

        last = nullopt;
        for (int i = (int)marketsOfDay.size() - 1; i >= 0; i--) {
            const auto [L, M] = marketsOfDay[i];
            const int Lc = idxs[i];

            int R = max(queryResults[i],
                        last ? last->first - U * (last->second - L) : numeric_limits<int>::min()) +
                    M;

            revenues[Lc] = max(revenues[Lc], R);
            last = {R, L};
        }

        for (int i = 0; i < (int)marketsOfDay.size(); i++) {
            const auto [L, M] = marketsOfDay[i];
            const int Lc = idxs[i];

            upper.update(Lc, revenues[Lc] - U * L);
            lower.update(Lc, revenues[Lc] + D * L);
        }
    }

    cout << revenues[lower_bound(all(locs), S) - locs.begin()] << '\n';

    return 0;
}

Compilation message (stderr)

salesman.cpp: In function 'INPUT& operator>>(INPUT&, T&)':
salesman.cpp:113:5: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
  113 |     else if constexpr (is_integral_v<T>) i = in.ReadInt<T>(); return in; }
      |     ^~~~
salesman.cpp:113:63: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'else'
  113 |     else if constexpr (is_integral_v<T>) i = in.ReadInt<T>(); return in; }
      |                                                               ^~~~~~
salesman.cpp: In function 'OUTPUT& operator<<(OUTPUT&, T)':
salesman.cpp:120:5: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
  120 |     else if constexpr (is_integral_v<T>) out.WriteInt<T>(i); return out; }
      |     ^~~~
salesman.cpp:120:62: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'else'
  120 |     else if constexpr (is_integral_v<T>) out.WriteInt<T>(i); return out; }
      |                                                              ^~~~~~
salesman.cpp: In function 'int main()':
salesman.cpp:235:30: warning: 'last.std::pair<int, int>::first' may be used uninitialized in this function [-Wmaybe-uninitialized]
  235 |                         last ? last->first - U * (last->second - L) : numeric_limits<int>::min()) +
      |                         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
salesman.cpp:235:64: warning: 'last.std::pair<int, int>::second' may be used uninitialized in this function [-Wmaybe-uninitialized]
  235 |                         last ? last->first - U * (last->second - L) : numeric_limits<int>::min()) +
      |                                                  ~~~~~~~~~~~~~~^~~~

• Subtask 1: 100 / 100