Submission #277788

#	Time	Username	Problem	Language	Result	Execution time	Memory
277788		ASDF123	Seats (IOI18_seats)	C++14	11 / 100	2552 ms	262148 KiB

seats

#include <seats.h>
#include <bits/stdc++.h>
#define chkmax(a, b) a = max(a, (b))
#define chkmin(a, b) a = min(a, (b))
#define szof(s) (int)s.size()
#define pii pair<int, int>
#define fr first
#define sc second
using namespace std;

const int INF = 0x3f3f3f3f;
const int N = 1e6 + 5;
int r[N], c[N];
int ourH, ourW;
set <int> row[N], col[N];

struct node {
  int mn, mx;
  node() {
    mn = INF;
    mx = -INF;
  }
};

struct Tree {
  vector <node> tree;
  Tree() {
    tree.resize(1e6 * 4);
  }
  void upd(int pos, int val, int v = 1, int tl = 1, int tr = 1e6) {
    if (tl == tr) {
      tree[v].mn = tree[v].mx = val;
      return;
    }
    int mid = tl + tr >> 1;
    if (pos <= mid) {
      upd(pos, val, v + v, tl, mid);
    }
    else {
      upd(pos, val, v + v + 1, mid + 1, tr);
    }
    tree[v].mn = min(tree[v + v].mn, tree[v + v + 1].mn);
    tree[v].mx = max(tree[v + v].mx, tree[v + v + 1].mx);
  }
  pii merge(pii a, pii b) {
    return { min(a.fr, b.fr), max(a.sc, b.sc) };
  }
  pii getpair(int l, int r, int v = 1, int tl = 1, int tr = 1e6) {
    if (l <= tl && tr <= r) {
      return { tree[v].mn, tree[v].mx };
    }
    if (l > tr || tl > r) {
      return { INF, -INF };
    }
    int mid = tl + tr >> 1;
    return merge(getpair(l, r, v + v, tl, mid), getpair(l, r, v + v + 1, mid + 1, tr));
  }
  int get(int l, int r, int type, int v = 1, int tl = 1, int tr = 1e6) {
    if (l <= tl && tr <= r) {
      if (type == 1) {
        return tree[v].mn;
      }
      else {
        return tree[v].mx;
      }
    }
    if (l > tr || tl > r) {
      if (type == 1) {
        return INF;
      }
      else {
        return -INF;
      }
    }
    int mid = tl + tr >> 1;
    int lft = get(l, r, type, v + v, tl, mid);
    int rgt = get(l, r, type, v + v + 1, mid + 1, tr);
    if (type == 1) {
      return min(lft, rgt);
    }
    else {
      return max(lft, rgt);
    }
  }
} rows, columns;

void give_initial_chart(int H, int W, std::vector<int> R, std::vector<int> C) {
  for (int i = 0; i < H * W; i++) {
    r[i + 1] = R[i] + 1;
    c[i + 1] = C[i] + 1;
  }
  ourH = H;
  ourW = W;
  for (int i = 1; i <= ourH * ourW; i++) {
    rows.upd(i, r[i]);
    columns.upd(i, c[i]);
  }
  for (int i = 1; i <= ourH * ourW; i++) {
    row[r[i]].insert(i);
    col[c[i]].insert(i);
  }
}

bool good(int pos) {
  pii a = rows.getpair(1, pos);
  pii b = columns.getpair(1, pos);
  return (a.sc - a.fr + 1) * (b.sc - b.fr + 1) == pos;
}

int subtask3(int a, int b) {
  a++, b++;
  row[r[a]].erase(a);
  col[c[a]].erase(a);
  row[r[b]].erase(b);
  col[c[b]].erase(b);
  swap(r[a], r[b]);
  swap(c[a], c[b]);
  row[r[a]].insert(a);
  col[c[a]].insert(a);
  row[r[b]].insert(b);
  row[c[b]].insert(b);
  rows.upd(a, r[a]);
  columns.upd(a, c[a]);
  rows.upd(b, r[b]);
  columns.upd(b, c[b]);
  set <int> used;
  for (int i = 1; i <= ourH; i++) {
    int best = *row[i].begin();
    if (used.find(best) == used.end() && good(best)) {
      used.insert(best);
    }
  }
  for (int i = 1; i <= ourW; i++) {
    int best = *col[i].begin();
    if (used.find(best) == used.end() && good(best)) {
      used.insert(best);
    }
  }
  return szof(used);
}

int swap_seats(int a, int b) { // answer after swap
  if (ourH * ourW <= 10000) {
    int ans = 0;
    a++, b++;
    swap(r[a], r[b]);
    swap(c[a], c[b]);
    node R, C;
    for (int i = 1; i <= ourH * ourW; i++) {
      chkmin(R.mn, r[i]);
      chkmax(R.mx, r[i]);
      chkmin(C.mn, c[i]);
      chkmax(C.mx, c[i]);
      if ((R.mx - R.mn + 1) * (C.mx - C.mn + 1) == i) {
        ans++;
      }
    }
    return ans;
  }
  if (ourH <= 1000 && ourW <= 1000) {
    return subtask3(a, b);
  }
  assert(false);
}

//signed main() {
//  vector <int> vecC, vecR;
//  int h, w;
//  cin >> h >> w;
//  vecC.resize(h * w);
//  vecR.resize(h * w);
//  for (int i = 0; i < h * w; i++) {
//    cin >> vecR[i] >> vecC[i];
//  }
//
//  give_initial_chart(h, w, vecR, vecC);
//  int Q;
//  cin >> Q;
//  while (Q--) {
//    int a, b;
//    cin >> a >> b;
//    cout << swap_seats(a, b) << endl;
//  }
//}

Compilation message (stderr)

seats.cpp: In member function 'void Tree::upd(int, int, int, int, int)':
seats.cpp:35:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   35 |     int mid = tl + tr >> 1;
      |               ~~~^~~~
seats.cpp: In member function 'std::pair<int, int> Tree::getpair(int, int, int, int, int)':
seats.cpp:55:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   55 |     int mid = tl + tr >> 1;
      |               ~~~^~~~
seats.cpp: In member function 'int Tree::get(int, int, int, int, int, int)':
seats.cpp:75:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   75 |     int mid = tl + tr >> 1;
      |               ~~~^~~~

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