Submission #659000

#	Time	Username	Problem	Language	Result	Execution time	Memory
659000		600Mihnea	New Home (APIO18_new_home)	C++17	5 / 100	5066 ms	17308 KiB

new_home

bool home = 0;

#include <bits/stdc++.h>

using namespace std;

struct Store {
  int x;
  int type;
  int first_time;
  int last_time;
};

struct Query {
  int x;
  int t;
};

const int N = (int) 3e5 + 7;
int n;
int k;
int q;
vector<int> whereType[N];
Store stores[N];
Query queries[N];
vector<int> events;

int getTimeOfEvent(int i) {
  if (i >= 1) {
    assert(1 <= i && i <= n);
    return stores[i].first_time;
  } else {
    i *= -1;
    assert(1 <= i && i <= n);
    return stores[i].last_time + 1;
  }
}

bool cmpEvents(int i, int j) {
  return getTimeOfEvent(i) < getTimeOfEvent(j);
}

struct Position {
  int i;
};

bool operator < (Position a, Position b) {
  int i = a.i, j = b.i;
  if (stores[i].x == stores[j].x) {
    return i < j;
  } else {
    return stores[i].x < stores[j].x;
  }
}

void addSegment(int first_time, int last_time, int i, int j) {
  assert(1 <= i && i <= n + 2);
  assert(1 <= j && j <= n + 2);
  if (i > n || j > n) {
    return;
  }
  assert(1 <= i && i <= n);
  assert(1 <= j && j <= n);
}

int main() {
  if (home) {
    freopen ("input.txt", "r", stdin);
  } else {
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  }
  {
    /// Read
    cin >> n >> k >> q;
    for (int i = 1; i <= n; i++) {
      cin >> stores[i].x >> stores[i].type >> stores[i].first_time >> stores[i].last_time;
    }
    for (int i = 1; i <= q; i++) {
      cin >> queries[i].x >> queries[i].t;
    }
  }
  {
    /// Normalize time
    vector<int> interestingTimes;
    for (int i = 1; i <= q; i++) {
      interestingTimes.push_back(queries[i].t);
    }
    sort(interestingTimes.begin(), interestingTimes.end());
    interestingTimes.resize(unique(interestingTimes.begin(), interestingTimes.end()) - interestingTimes.begin());
    for (int i = 1; i <= q; i++) {
      queries[i].t = lower_bound(interestingTimes.begin(), interestingTimes.end(), queries[i].t) - interestingTimes.begin();
    }
    int y = 0;
    for (int i = 1; i <= n; i++) {
      stores[i].first_time = lower_bound(interestingTimes.begin(), interestingTimes.end(), stores[i].first_time) - interestingTimes.begin();
      stores[i].last_time = lower_bound(interestingTimes.begin(), interestingTimes.end(), stores[i].last_time + 1) - interestingTimes.begin() - 1;
      if (stores[i].first_time <= stores[i].last_time) {
        stores[++y] = stores[i];
      }
    }
    n = y;
  }

  {
    /// Some more computation
    for (int i = 1; i <= n; i++) {
      whereType[stores[i].type].push_back(i);
    }
    stores[n + 1].x = -((int) 1e8 + 7);
    stores[n + 2].x = +((int) 1e8 + 7);
    for (int type = 1; type <= k; type++) {
      set<Position> positions;
      map<pair<int, int>, int> sinceWhen;
      positions.insert({n + 1});
      positions.insert({n + 2});

      sinceWhen[{n + 1, n + 2}] = 0;
      events.clear();
      for (auto &i : whereType[type]) {
        events.push_back(+i);
        events.push_back(-i);
      }
      sort(events.begin(), events.end(), cmpEvents);
      int l_events = 0;
      while (l_events < (int) events.size()) {
        int r_events = l_events;
        while (r_events + 1 < (int) events.size() && getTimeOfEvent(events[r_events + 1]) == getTimeOfEvent(events[r_events])) {
          r_events++;
        }
        int current_time = getTimeOfEvent(events[l_events]);
        for (int iter_events = l_events; iter_events <= r_events; iter_events++) {
          int i = events[iter_events];

          if (i >= 1) {
            assert(1 <= i && i <= n);
            positions.insert({i});


            auto it = positions.find({i});
            assert(it != positions.end());
            auto nxt = it;
            auto ant = it;
            nxt++;
            assert(nxt != positions.end());
            assert(ant != positions.begin());
            ant--;

            assert(sinceWhen.count({ant->i, nxt->i}));
            sinceWhen.erase({ant->i, nxt->i});
            assert(!sinceWhen.count({ant->i, nxt->i}));
            sinceWhen[{ant->i, it->i}] = current_time;
            sinceWhen[{it->i, nxt->i}] = current_time;
          } else {
            i *= -1;
            assert(1 <= i && i <= n);
            assert(positions.count({i}));



            auto it = positions.find({i});
            assert(it != positions.end());
            auto nxt = it;
            auto ant = it;
            nxt++;
            assert(nxt != positions.end());
            assert(ant != positions.begin());
            ant--;

            assert(!sinceWhen.count({ant->i, nxt->i}));
            sinceWhen[{ant->i, nxt->i}] = current_time;
            assert(sinceWhen.count({ant->i, nxt->i}));

            assert(sinceWhen.count({ant->i, it->i}));
            sinceWhen.erase({ant->i, it->i});

            assert(sinceWhen.count({it->i, nxt->i}));
            sinceWhen.erase({it->i, nxt->i});

            positions.erase({i});
          }
        }
        l_events = r_events + 1;
      }
    }
  }
  {
    /// Brute
    for (int iq = 1; iq <= q; iq++) {
      int maxDist = 0;
      for (int t = 1; t <= k; t++) {
        int minDist = (int) 1e9 + 7;
        for (auto &i : whereType[t]) {
          if (stores[i].first_time <= queries[iq].t && queries[iq].t <= stores[i].last_time) {
            minDist = min(minDist, abs(stores[i].x - queries[iq].x));
          }
        }
        maxDist = max(maxDist, minDist);
      }
      if (maxDist == (int) 1e9 + 7) {
        maxDist = -1;
      }
      cout << maxDist << "\n";
    }
  }
  return 0;
}

Compilation message (stderr)

new_home.cpp: In function 'int main()':
new_home.cpp:68:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   68 |     freopen ("input.txt", "r", stdin);
      |     ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 0 / 7
• Subtask 3: 0 / 10
• Subtask 4: 0 / 23
• Subtask 5: 0 / 35
• Subtask 6: 0 / 20