Submission #229959

#	Time	Username	Problem	Language	Result	Execution time	Memory
229959		fedoseevtimofey	Seats (IOI18_seats)	C++14	11 / 100	4094 ms	71776 KiB

seats

#include "seats.h"
#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <deque>
#include <stack>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <cstring>
#include <cmath>
#include <cstdlib>
#include <algorithm>
#include <random>
#include <iomanip>
#include <functional>
#include <cassert>
 
using namespace std;
 
typedef long long ll;

const int N = 1e6 + 7;
const int Inf = 1e9 + 7;
 
struct Node {
  int mn, cnt;
  Node(int x) {
    mn = x;
    cnt = 1;
  }
  Node() {
    mn = Inf;
    cnt = 0;
  }
  Node operator +(const Node &other) {
    Node res;
    res.mn = min(mn, other.mn);
    if (res.mn == mn) res.cnt += cnt;
    if (res.mn == other.mn) res.cnt += other.cnt;
    return res;
  }
};  
 
Node t[4 * N];
int mod[4 * N];
 
void update(int v, int val) {
  t[v].mn += val;
  mod[v] += val;
}
 
void push(int v) {
  if (mod[v]) {
    update(2 * v + 1, mod[v]);
    update(2 * v + 2, mod[v]);
    mod[v] = 0;
  }
}
 
void build(int l, int r, int v, vector <int> &a) {
  if (l == r) {
    t[v] = Node(a[l]);
  } else {
    int m = (l + r) >> 1;
    build(l, m, 2 * v + 1, a);
    build(m + 1, r, 2 * v + 2, a);
    t[v] = t[2 * v + 1] + t[2 * v + 2];
  }
}
 
void modify(int ql, int qr, int val, int l, int r, int v) {
  if (qr < l || r < ql) return;
  if (ql <= l && r <= qr) {
    update(v, val);
  } else {
    push(v);
    int m = (l + r) >> 1;
    modify(ql, qr, val, l, m, 2 * v + 1);
    modify(ql, qr, val, m + 1, r, 2 * v + 2);
    t[v] = t[2 * v + 1] + t[2 * v + 2];
  }
}
 
vector <vector <int>> a;
vector <int> r, c;
int n, m;

bool ok(int x, int y) {
  return 0 <= x && x < n && 0 <= y && y < m;
}

vector <int> dx = {0, 0, -1, 1};
vector <int> dy = {-1, 1, 0, 0};

void add(int x, int y, int s) {
  vector <int> who;
  for (int k = 0; k < 4; ++k) {
    int nx = x + dx[k];
    int ny = y + dy[k];
    if (ok(nx, ny)) {
      who.push_back(a[nx][ny]);
    }
  }
  sort(who.begin(), who.end());
  int l_good = 0;
  int r_good = a[x][y] - 1;
  if ((int)who.size() >= 2) {
    r_good = min(r_good, who[1] - 1);
  }
  if (l_good <= r_good) {
    modify(l_good, r_good, -1 * s, 0, n * m - 1, 0);
  }
  l_good = a[x][y];
  if ((int)who.size() >= 2) {
    l_good = max(l_good, who[1]);
  } else {
    l_good = Inf;
  }
  r_good = n * m - 1;
  if ((int)who.size() >= 3) {
    r_good = who[2] - 1;
  }
  if (l_good <= r_good) {
    modify(l_good, r_good, 1 * s, 0, n * m - 1, 0);
  }
  l_good = a[x][y];
  r_good = n * m - 1;
  if ((int)who.size() >= 2) {
    r_good = who[1] - 1;
  }
  if (l_good <= r_good) {
    modify(l_good, r_good, 100 * s, 0, n * m - 1, 0);
  }
}
 
void give_initial_chart(int N, int M, vector<int> R, vector<int> C) {
  n = N, m = M;
  r = R, c = C;
  a.resize(n, vector <int> (m));
  for (int i = 0; i < n * m; ++i) {
    a[r[i]][c[i]] = i;
  }
  vector <int> start(n * m);
  for (int i = 0; i < n * m; ++i) {
    start[i] = n * m - (i + 1) - 4;
  }
  build(0, n * m - 1, 0, start);
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < m; ++j) {
      add(i, j, 1);
    }
  }
}
 
int swap_seats(int x, int y) {
  set <pair <int, int>> go;
  for (int k = 0; k < 4; ++k) {
    int nx = r[x] + dx[k];
    int ny = c[x] + dy[k];
    if (ok(nx, ny)) {
      go.insert({nx, ny});
    }
  }
  go.insert({r[x], c[x]});

  for (int k = 0; k < 4; ++k) {
    int nx = r[y] + dx[k];
    int ny = c[y] + dy[k];
    if (ok(nx, ny)) {
      go.insert({nx, ny});
    }
  }
  go.insert({r[y], c[y]});

  for (auto p : go) {
    add(p.first, p.second, -1);
  }
  swap(a[r[x]][c[x]], a[r[y]][c[y]]);
  swap(r[x], r[y]);
  swap(c[x], c[y]);
  for (auto p : go) {
    add(p.first, p.second, 1);
  }
  int ans = (t[0].mn == 0 ? t[0].cnt : 0);
  
  int min_r = n, max_r = 0, min_c = m, max_c = 0;
  for (int i = 0; i < n * m; ++i) {
    min_r = min(min_r, r[i]);
    max_r = max(max_r, r[i]);
    min_c = min(min_c, c[i]);
    max_c = max(max_c, c[i]);
    if ((min_r == max_r || min_c == max_c) && (max_r - min_r + 1) * (max_c - min_c + 1) == i + 1) {
      ++ans;
    }
  }
  return ans;
}
 
#ifdef LOCAL
 
int main() {
  ios_base::sync_with_stdio(false); cin.tie(0);
#ifdef LOCAL
  freopen("input.txt", "r", stdin);
#endif
  int n, m, q;
  cin >> n >> m >> q;
  vector <int> R(n * m), C(n * m);
  for (int i = 0; i < n * m; ++i) {
    cin >> R[i] >> C[i];
  }
  vector <int> aq(q), bq(q);
  for (int i = 0; i < q; ++i) {
    cin >> aq[i] >> bq[i];
  }
  give_initial_chart(n, m, R, C);
  for (int j = 0; j < q; ++j) {
    cout << swap_seats(aq[j], bq[j]) << '\n';
  }
}
 
#endif

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