oj.uz

Submission #499190

# Submission time Handle Problem Language Result Execution time Memory
499190 2021-12-27T12:30:25 Z 600Mihnea Golf (JOI17_golf) C++17
30 / 100
 10000 ms 89768 KB 
#include <bits/stdc++.h>

using namespace std;

#define y1 ynot1

typedef long long ll;
typedef long double ld;

struct Box {
  int xmin;
  int xmax;
  int ymin;
  int ymax;

};

const int N = 100000 + 7;
const int INF = (int) 1e9 + 7;

int n;
int x1;
int y1;
int x2;
int y2;
Box boxes[N];

void normalization() {
  map<int, int> mx, my;

  for (int i = 0; i <= n + 1; i++) {
    mx[boxes[i].xmin] = 0;
    mx[boxes[i].xmax] = 0;

    my[boxes[i].ymin] = 0;
    my[boxes[i].ymax] = 0;
  }

  int c = 0;
  for (auto &it : mx) {
    it.second = ++c;
  }

  c = 0;
  for (auto &it : my) {
    it.second = ++c;
  }


  for (int i = 0; i <= n + 1; i++) {
    boxes[i].xmin = mx[boxes[i].xmin];
    boxes[i].xmax = mx[boxes[i].xmax];

    boxes[i].ymin = my[boxes[i].ymin];
    boxes[i].ymax = my[boxes[i].ymax];
  }
}

struct Segment {
  int where;
  int low;
  int high;
  int e_low;
  int e_high;
  int dp;
};

/**

segment tree of lasts

**/

struct Node {
  int mn;
  int mx;
};

Node operator + (Node a, Node b) {
  return {min(a.mn, b.mn), max(a.mx, b.mx)};
}

const Node non = {2 * N, 0};
Node segt1[8 * N];
Node lazy1[8 * N];

void push(int v, int tl, int tr) {
  if (lazy1[v].mn == non.mn && lazy1[v].mx == non.mx) {
    return;
  }

  segt1[v] = segt1[v] + lazy1[v];

  if (tl < tr) {
    lazy1[2 * v] = lazy1[2 * v] + lazy1[v];
    lazy1[2 * v + 1] = lazy1[2 * v + 1] + lazy1[v];
  }

  lazy1[v] = non;
}

void updsegt1(int v, int tl, int tr, int l, int r, int x) {
  push(v, tl, tr);
  if (tr < l || r < tl) {
    return;
  }
  if (l <= tl && tr <= r) {
    lazy1[v] = lazy1[v] + Node{x, x};
    push(v, tl, tr);
    return;
  }
  int tm = (tl + tr) / 2;
  updsegt1(2 * v, tl, tm, l, r, x);
  updsegt1(2 * v + 1, tm + 1, tr, l, r, x);
  segt1[v] = segt1[2 * v] + segt1[2 * v + 1];
}

void updsegt1(int l, int r, int x) {
  if (l > r) {
    return;
  }
  assert(1 <= l && l <= r && r <= 2 * (n + 2));
  updsegt1(1, 1, 2 * (n + 2), l, r, x);
}

Node getsegt1(int v, int tl, int tr, int l, int r) {
  push(v, tl, tr);
  if (tr < l || r < tl) {
    return non;
  }
  if (l <= tl && tr <= r) {
    return segt1[v];
  }
  int tm = (tl + tr) / 2;
  return getsegt1(2 * v, tl, tm, l, r) + getsegt1(2 * v + 1, tm + 1, tr, l, r);
}

Node getsegt1(int l, int r) {
  return getsegt1(1, 1, 2 * (n + 2), l, r);
}

void clr() {
  for (int i = 0; i < 8 * N; i++) {
    segt1[i] = non;
    lazy1[i] = non;
  }
}


vector<vector<Segment>> segs;
vector<Segment> xSegs;
vector<Segment> ySegs;

bool cmpextlowX(int i, int j) {
  return xSegs[i].low < xSegs[j].low;
}

bool cmpexthighX(int i, int j) {
  return xSegs[i].high > xSegs[j].high;
}

bool cmpextY(int i, int j) {
  return ySegs[i].where < ySegs[j].where;
}

bool cmp(int i, int j) {
  return xSegs[i].e_low < xSegs[j].e_low;
}

void calculateextensions() {

  for (int step = 1; step <= 2; step++) {
    /// calculate x segs
    for (int i = 0; i <= n + 1; i++) {
      xSegs.push_back({boxes[i].ymin, boxes[i].xmin, boxes[i].xmax, 0, 2 * N, -1});
      xSegs.push_back({boxes[i].ymax, boxes[i].xmin, boxes[i].xmax, 0, 2 * N, -1});
    }

    for (int i = 0; i <= n + 1; i++) {
      swap(boxes[i].xmin, boxes[i].ymin);
      swap(boxes[i].xmax, boxes[i].ymax);
    }

    swap(xSegs, ySegs);
  }

  assert((int) xSegs.size() == 2 * (n + 2));
  assert((int) ySegs.size() == 2 * (n + 2));

  for (int step = 1; step <= 2; step++) {
    /// compute the extensions

    {
      vector<int> ordx(2 * (n + 2)), ordy;
      iota(ordx.begin(), ordx.end(), 0);
      ordy = ordx;
      sort(ordx.begin(), ordx.end(), cmpextlowX);
      sort(ordy.begin(), ordy.end(), cmpextY);

      {
        clr();
        int ptr = 0;
        for (int it = 0; it < 2 * (n + 2); it++) {
          int i = ordx[it];


          while (ptr < 2 * (n + 2) && ySegs[ordy[ptr]].where < xSegs[i].low) {
            updsegt1(ySegs[ordy[ptr]].low + 1, ySegs[ordy[ptr]].high - 1, ySegs[ordy[ptr]].where);
            ptr++;
          }

          xSegs[i].e_low = getsegt1(xSegs[i].where, xSegs[i].where).mx;
        }
      }

      {
        reverse(ordx.begin(), ordx.end()); /// optimization, daca nu merge, incearca cmpexthighX
        reverse(ordy.begin(), ordy.end());

        clr();
        int ptr = 0;
        for (int it = 0; it < 2 * (n + 2); it++) {
          int i = ordx[it];


          while (ptr < 2 * (n + 2) && ySegs[ordy[ptr]].where > xSegs[i].high) {
            updsegt1(ySegs[ordy[ptr]].low + 1, ySegs[ordy[ptr]].high - 1, ySegs[ordy[ptr]].where);
            ptr++;
          }

          xSegs[i].e_high = getsegt1(xSegs[i].where, xSegs[i].where).mn;
        }
      }

    }


    /// checker

    for (auto &it : xSegs) {
      assert(it.e_low <= it.low);
      assert(it.high <= it.e_high);
    }

    swap(xSegs, ySegs);
  }
  segs.push_back(xSegs);
  segs.push_back(ySegs);
}

queue<pair<int, int>> q;
bool deja[2][2 * N];

void addToQ(int type, int index, int value) {
  deja[type][index] = 1;
  assert(0 <= type && type < 2);
  assert(0 <= index && index < (int) segs[type].size());
  assert(segs[type][index].dp == -1);
  segs[type][index].dp = value;
  q.push({type, index});
}

struct Snode {
  int index;
  int l;
  int r;
};

bool operator < (Snode a, Snode b) {
  if (a.l != b.l) {
    return a.l < b.l;
  }
  return a.index < b.index;
}

set<Snode> guys[2][2 * N];
int cnt[2][8 * N];
vector<int> now;

set<int> ct;

void addToSegt(int type, int v, int tl, int tr, int i, Snode node) {
  if (tr < i || i < tl) {
    return;
  }
  if (tl == tr) {
    guys[type][tl].insert(node);
    assert(!ct.count(node.index));
    ct.insert(node.index);

    cnt[type][v] = (int) guys[type][tl].size();
    return;
  }
  int tm = (tl + tr) / 2;
  addToSegt(type, 2 * v, tl, tm, i, node);
  addToSegt(type, 2 * v + 1, tm + 1, tr, i, node);
  cnt[type][v] = cnt[type][2 * v] + cnt[type][2 * v + 1];
}

void del(int type, int v, int tl, int tr, int l, int r, int i) {
  if (cnt[type][v] == 0) {
    return;
  }
  if (tr < l || r < tl) {
    return;
  }
  if (tl == tr) {
    while (!guys[type][tl].empty()) {
      auto it = guys[type][tl].begin();
      if (it->l <= i && it->r >= i) {
        if (!deja[type][it->index]) now.push_back(it->index);
        guys[type][tl].erase(it);
      } else {
        break;
      }
    }
    while (!guys[type][tl].empty()) {
      auto it = guys[type][tl].lower_bound({-1, i + 1, -1});
      if (it == guys[type][tl].begin()) {
        break;
      }
      it--;
      assert(it->l <= i);
      if (it->l <= i && it->r >= i) {
        if (!deja[type][it->index]) now.push_back(it->index);
        guys[type][tl].erase(it);
      } else {
        break;
      }
    }
    cnt[type][v] = (int) guys[type][tl].size();
    return;
  }
  int tm = (tl + tr) / 2;
  del(type, 2 * v, tl, tm, l, r, i);
  del(type, 2 * v + 1, tm + 1, tr, l, r, i);
  cnt[type][v] = cnt[type][2 * v] + cnt[type][2 * v + 1];
}

signed main() {
  ios::sync_with_stdio(0); cin.tie(0);

  ///freopen ("input", "r", stdin);

  cin >> x1 >> y1 >> x2 >> y2;
  cin >> n;
  for (int i = 1; i <= n; i++) {
    cin >> boxes[i].xmin >> boxes[i].xmax >> boxes[i].ymin >> boxes[i].ymax;
  }

  boxes[0].xmin = boxes[0].xmax = x1;
  boxes[0].ymin = boxes[0].ymax = y1;

  boxes[n + 1].xmin = boxes[n + 1].xmax = x2;
  boxes[n + 1].ymin = boxes[n + 1].ymax = y2;

  normalization(); /// do it later

  calculateextensions();


  if (n > 1000) {
    /// exit(0); /// I wanted to measure the first part of the algorithm
  }

  addToQ(0, 0, 1);
  addToQ(0, 1, 1);
  addToQ(1, 0, 1);
  addToQ(1, 1, 1);

  /*for (int type = 0; type < 2; type++) {
    xSegs = segs[type];
    vector<int> inds(2 * (n + 2));
    iota(inds.begin(), inds.end(), 0);
   /// assert((int) inds.size() == (int) xSegs.size());
   // continue;
    sort(inds.begin(), inds.end(), cmp);
    map<int, int> last;
    for (auto &it : inds) {
      assert(last[xSegs[it].where] <= xSegs[it].e_high);
      last[xSegs[it].where] = xSegs[it].e_high;
    }
  }*/
  for (int type = 0; type < 2; type++) {
    for (int i = 0; i < 2 * (n + 2); i++) {
      addToSegt(type, 1, 1, 2 * (n + 2), segs[type][i].where, {i, segs[type][i].e_low, segs[type][i].e_high});
    }
    ct.clear();
  }


  while (!q.empty()) {
    auto itQ = q.front();
    q.pop();
    int type = itQ.first;
    int index = itQ.second;


    int dp = segs[type][index].dp;

    assert(2 * (n + 2) == (int) segs[type ^ 1].size());

    now.clear();
    del(type ^ 1, 1, 1, 2 * (n + 2), segs[type][index].e_low, segs[type][index].e_high, segs[type][index].where);

    for (auto &j : now) {
      addToQ(type ^ 1, j, segs[type][index].dp + 1);
    }
  }

  for (auto &v : segs) {
    for (auto &seg : v) {
      assert(seg.dp != -1);
    }
  }

  x2 = boxes[n + 1].xmin;
  y2 = boxes[n + 1].ymin;

  int sol = INF;

  swap(x2, y2);

  for (auto &v : segs) {
    for (auto &seg : v) {
      if (x2 == seg.where && seg.e_low <= y2 && y2 <= seg.e_high) {
        sol = min(sol, seg.dp);
      }
    }
    swap(x2, y2);
  }

  cout << sol << "\n";


  return 0;
}

Compilation message

golf.cpp: In function 'int main()':
golf.cpp:399:9: warning: unused variable 'dp' [-Wunused-variable]
  399 |     int dp = segs[type][index].dp;
      |         ^~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 31564 KB Output is correct
2 Correct 18 ms 31652 KB Output is correct
3 Correct 18 ms 31632 KB Output is correct
4 Correct 18 ms 31616 KB Output is correct
5 Correct 36 ms 32248 KB Output is correct
6 Correct 31 ms 32244 KB Output is correct
7 Correct 31 ms 32224 KB Output is correct
8 Correct 36 ms 32220 KB Output is correct
9 Correct 38 ms 32232 KB Output is correct
10 Correct 30 ms 32248 KB Output is correct
11 Correct 31 ms 32196 KB Output is correct
12 Correct 30 ms 32244 KB Output is correct
13 Correct 29 ms 32188 KB Output is correct
14 Correct 31 ms 32220 KB Output is correct
15 Correct 26 ms 31820 KB Output is correct
16 Correct 50 ms 32076 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 31564 KB Output is correct
2 Correct 18 ms 31652 KB Output is correct
3 Correct 18 ms 31632 KB Output is correct
4 Correct 18 ms 31616 KB Output is correct
5 Correct 36 ms 32248 KB Output is correct
6 Correct 31 ms 32244 KB Output is correct
7 Correct 31 ms 32224 KB Output is correct
8 Correct 36 ms 32220 KB Output is correct
9 Correct 38 ms 32232 KB Output is correct
10 Correct 30 ms 32248 KB Output is correct
11 Correct 31 ms 32196 KB Output is correct
12 Correct 30 ms 32244 KB Output is correct
13 Correct 29 ms 32188 KB Output is correct
14 Correct 31 ms 32220 KB Output is correct
15 Correct 26 ms 31820 KB Output is correct
16 Correct 50 ms 32076 KB Output is correct
17 Correct 34 ms 32232 KB Output is correct
18 Correct 36 ms 32156 KB Output is correct
19 Correct 33 ms 32156 KB Output is correct
20 Correct 35 ms 32148 KB Output is correct
21 Correct 39 ms 32204 KB Output is correct
22 Correct 35 ms 32240 KB Output is correct
23 Correct 36 ms 32188 KB Output is correct
24 Correct 43 ms 32196 KB Output is correct
25 Correct 41 ms 32196 KB Output is correct
26 Correct 35 ms 32204 KB Output is correct
27 Correct 30 ms 31876 KB Output is correct
28 Correct 53 ms 32160 KB Output is correct
29 Correct 54 ms 32176 KB Output is correct

Subtask #3
0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 31564 KB Output is correct
2 Correct 18 ms 31652 KB Output is correct
3 Correct 18 ms 31632 KB Output is correct
4 Correct 18 ms 31616 KB Output is correct
5 Correct 36 ms 32248 KB Output is correct
6 Correct 31 ms 32244 KB Output is correct
7 Correct 31 ms 32224 KB Output is correct
8 Correct 36 ms 32220 KB Output is correct
9 Correct 38 ms 32232 KB Output is correct
10 Correct 30 ms 32248 KB Output is correct
11 Correct 31 ms 32196 KB Output is correct
12 Correct 30 ms 32244 KB Output is correct
13 Correct 29 ms 32188 KB Output is correct
14 Correct 31 ms 32220 KB Output is correct
15 Correct 26 ms 31820 KB Output is correct
16 Correct 50 ms 32076 KB Output is correct
17 Correct 34 ms 32232 KB Output is correct
18 Correct 36 ms 32156 KB Output is correct
19 Correct 33 ms 32156 KB Output is correct
20 Correct 35 ms 32148 KB Output is correct
21 Correct 39 ms 32204 KB Output is correct
22 Correct 35 ms 32240 KB Output is correct
23 Correct 36 ms 32188 KB Output is correct
24 Correct 43 ms 32196 KB Output is correct
25 Correct 41 ms 32196 KB Output is correct
26 Correct 35 ms 32204 KB Output is correct
27 Correct 30 ms 31876 KB Output is correct
28 Correct 53 ms 32160 KB Output is correct
29 Correct 54 ms 32176 KB Output is correct
30 Execution timed out 10008 ms 89768 KB Time limit exceeded
31 Halted 0 ms 0 KB -