Submission #619018

#	Time	Username	Problem	Language	Result	Execution time	Memory
619018		evenvalue	Seats (IOI18_seats)	C++17	11 / 100	4062 ms	64452 KiB

seats

#include "seats.h"
#include <bits/stdc++.h>
using namespace std;

template<typename T>
using min_heap = priority_queue<T, vector<T>, greater<T>>;
template<typename T>
using max_heap = priority_queue<T, vector<T>, less<T>>;

using int64 = long long;
using ld = long double;

constexpr int kInf = 1e9 + 10;
constexpr int64 kInf64 = 1e15 + 10;
constexpr int kMod = 1e9 + 7;

template<class node, class F = std::function<node(const node &, const node &)>>
class SegTree {
  int n = 0;
  std::vector<node> t;
  F unite;

  void build(const int x, const int l, const int r, const std::vector<node> &a) {
    if (l == r) {
      t[x] = a[l];
      return;
    }
    const int mid = (l + r) / 2;
    const int y = 2 * (mid - l + 1) + x;
    build(x + 1, l, mid, a);
    build(y, mid + 1, r, a);
    t[x] = unite(t[x + 1], t[y]);
  }

  void update(const int x, const int l, const int r, const int p, const node &v) {
    if (l == p and p == r) {
      t[x] = v;
      return;
    }
    const int mid = (l + r) / 2;
    const int y = 2 * (mid - l + 1) + x;
    if (p <= mid) {
      update(x + 1, l, mid, p, v);
    } else {
      update(y, mid + 1, r, p, v);
    }
    t[x] = unite(t[x + 1], t[y]);
  }

  node query(const int x, const int l, const int r, const int ql, const int qr) const {
    if (ql <= l and r <= qr) {
      return t[x];
    }
    const int mid = (l + r) / 2;
    const int y = 2 * (mid - l + 1) + x;
    if (qr <= mid) {
      return query(x + 1, l, mid, ql, qr);
    } else if (mid < ql) {
      return query(y, mid + 1, r, ql, qr);
    } else {
      return unite(query(x + 1, l, mid, ql, qr), query(y, mid + 1, r, ql, qr));
    }
  }

public:
  SegTree() = default;
  explicit SegTree(const int n, const node e, F f) : n(n), t(2 * n - 1, e), unite(std::move(f)) {}
  explicit SegTree(const std::vector<node> &a, F f) : n(a.size()), t(2 * (a.size()) - 1), unite(std::move(f)) {
    build(0, 0, n - 1, a);
  }

  void set(const int p, const node &v) {
    assert(0 <= p and p < n);
    update(0, 0, n - 1, p, v);
  }

  node get(const int l, const int r) const {
    assert(0 <= l and l <= r and r < n);
    return query(0, 0, n - 1, l, r);
  }
};

int H, W;
vector<int> R, C;
SegTree<int> leftmost, rightmost, topmost, bottommost;

void give_initial_chart(int H_, int W_, std::vector<int> R_, std::vector<int> C_) {
  H = H_, W = W_;
  R = move(R_), C = move(C_);
  leftmost = SegTree<int>(C, [&](const int l, const int r) {
    return min(l, r);
  });
  rightmost = SegTree<int>(C, [&](const int l, const int r) {
    return max(l, r);
  });
  topmost = SegTree<int>(R, [&](const int l, const int r) {
    return min(l, r);
  });
  bottommost = SegTree<int>(R, [&](const int l, const int r) {
    return max(l, r);
  });
}

int count_beautiful_rectangles() {
  const int total_seats = H * W;
  int ans = 0;
  int l = kInf, r = -kInf, t = kInf, b = -kInf;
  for (int cur_seat = 0; cur_seat < total_seats; cur_seat++) {
    l = min(l, C[cur_seat]);
    r = max(r, C[cur_seat]);
    t = min(t, R[cur_seat]);
    b = max(b, R[cur_seat]);
    const int rect_size = (r - l + 1) * (b - t + 1);
    const bool beautiful = (cur_seat + 1 == rect_size);
    ans += beautiful;
  }
  return ans;
}

int swap_seats(int x, int y) {
  swap(R[x], R[y]);
  swap(C[x], C[y]);
  leftmost.set(x, C[x]), rightmost.set(x, C[x]);
  topmost.set(x, R[x]), bottommost.set(x, R[x]);
  leftmost.set(y, C[y]), rightmost.set(y, C[y]);
  topmost.set(y, R[y]), bottommost.set(y, R[y]);
  return count_beautiful_rectangles();
}

• Subtask 1: 5 / 5
• Subtask 2: 6 / 6
• Subtask 3: 0 / 20
• Subtask 4: 0 / 6
• Subtask 5: 0 / 33
• Subtask 6: 0 / 30