Submission #886534

#	Time	Username	Problem	Language	Result	Execution time	Memory
886534		vjudge1	Towers (NOI22_towers)	C++17	18 / 100	821 ms	121168 KiB

Main

#include <bits/stdc++.h>

using namespace std;

template<typename A, typename B>
string to_string(pair<A, B>);
string to_string(string S) {
  return '"' + S + '"';
}
string to_string(const char* c) {
  return to_string(string(c));
}
string to_string(bool b) {
  return (b ? "true" : "false");
}
template<size_t T>
string to_string(bitset<T> bs) {
  return bs.to_string();
}
string to_string(vector<bool> v) {
  string res = "{";
  for (int i = 0; i < int(v.size()); ++i) {
    if (int(res.size()) > 1) {
      res += ", ";
    }
    res += to_string(v[i]);
  }
  return res + "}";
}
template<typename T>
string to_string(T v) {
  string res = "{";
  for (auto e : v) {
    if (int(res.size()) > 1) {
      res += ", ";
    }
    res += to_string(e);
  }
  return res + "}";
}
template<typename A, typename B>
string to_string(pair<A, B> p) {
  return '(' + to_string(p.first) + ", " + to_string(p.second) + ')';
}
void debug_out() {
  cerr << endl;
}
template<typename H, typename... T>
void debug_out(H head, T... tail) {
  cerr << "  " << to_string(head);
  debug_out(tail...);
}

#ifdef DEBUG 
  #define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__) 
#else 
  #define debug(...) void(37)
#endif

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  int N;
  cin >> N;
  vector<int> X(N), Y(N);
  for (int i = 0; i < N; ++i) {
    cin >> X[i] >> Y[i];
    --X[i], --Y[i];
  }
  #ifdef LOCAL
    const int MAX = int(30);
  #else
    const int MAX = int(1e6);
  #endif
  vector<vector<int>> xs(MAX), ys(MAX);
  for (int i = 0; i < N; ++i) {
    xs[X[i]].push_back(i);
    ys[Y[i]].push_back(i);
  }
  vector<int> xid(N), yid(N);
  for (int i = 0; i < MAX; ++i) {
    sort(xs[i].begin(), xs[i].end(), [&](int x, int y) {  
      return Y[x] < Y[y];
    });
    sort(ys[i].begin(), ys[i].end(), [&](int x, int y) {
      return X[x] < X[y];
    });
    for (int j = 0; j < int(xs[i].size()); ++j) {
      xid[xs[i][j]] = j;
    }
    for (int j = 0; j < int(ys[i].size()); ++j) {
      yid[ys[i][j]] = j;
    }
  }
  vector<bool> used(N), only(N);
  for (int i = 0; i < MAX; ++i) {
    if (xs[i].empty()) continue;
    used[xs[i][0]] = true;
    used[xs[i].back()] = true;
    if (xs[i].size() == 1) {
      only[xs[i][0]] = true;
    }
  }
  debug(used);
  for (int i = MAX - 1; i > 0; --i) {
    vector<int> act;
    for (auto x : ys[i]) {
      if (used[x]) {
        act.push_back(x);
      }
    }
    debug(act);
    for (int j = 1; j < int(act.size()) - 1; ++j) {
      int e = act[j];
      used[e] = false;
      debug(e);
      if (!only[e]) {
        debug(xs[X[e]]);
        int prev = xid[e] - 1;
        if (prev >= 0) {
          int go = xs[X[e]][prev];
          if (used[go]) {
            only[go] = true;
          } else {
            used[go] = true;
          }
        }
      }
    }
  }
  debug(used);
  for (int i = 0; i < MAX; ++i) {
    vector<int> act;
    for (auto x : ys[i]) {
      if (used[x]) {
        act.push_back(x);
      }
    }
    for (int j = 1; j < int(act.size()) - 1; ++j) {
      int e = act[j];
      used[e] = false;
      if (!only[e]) {
        int prev = xid[e]  + 1;
        assert(prev < int(xs[X[e]].size()));
        int go = xs[X[e]][prev];
        if (used[go]) {
          only[go] = true;
        } else {
          used[go] = true;
        }
      }
    }
  }
  for (int i = 0; i < N; ++i) {
    cout << used[i];
  }
  cout << '\n';
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 11
• Subtask 3: 7 / 7
• Subtask 4: 6 / 6
• Subtask 5: 0 / 31
• Subtask 6: 0 / 21
• Subtask 7: 0 / 19