Submission #845050

#	Time	Username	Problem	Language	Result	Execution time	Memory
845050		tch1cherin	Palembang Bridges (APIO15_bridge)	C++17	0 / 100	0 ms	348 KiB

bridge

#include <bits/stdc++.h>
using namespace std;

struct fenwick {
  int size;
  vector<long long> tree;

  fenwick(int N) : size(N), tree(N + 1) {}

  void update(int i, int value) {
    for (i++; i <= size; i += i & -i) {
      tree[i] += value;
    }
  }

  long long query(int r) {
    long long ans = 0;
    for (; r > 0; r -= r & -r) {
      ans += tree[r];
    }
    return ans;
  }

  int lower_bound(long long value) {
    int pos = 0;
    for (int l = 20; l >= 0; l--) {
      if (pos + (1 << l) <= size && tree[pos + (1 << l)] < value) {
        pos += (1 << l);
        value -= tree[pos];
      }
    }
    return pos;
  }
};

int main() {
  cin.tie(nullptr)->sync_with_stdio(false);
  int K, N;
  cin >> K >> N;
  vector<char> P(N), Q(N);
  vector<int> S(N), T(N), G;
  long long ans = 0;
  vector<array<int, 2>> X;
  for (int i = 0; i < N; i++) {
    cin >> P[i] >> S[i] >> Q[i] >> T[i];
    if (P[i] > Q[i]) {
      swap(S[i], T[i]);
    }
    if (P[i] == Q[i]) {
      ans += abs(S[i] - T[i]);
    } else {  
      ans++;
      X.push_back({S[i], T[i]});
      G.push_back(S[i]);  
      G.push_back(T[i]);
    }
  }
  int M = (int)X.size();
  sort(G.begin(), G.end());
  G.resize(unique(G.begin(), G.end()) - G.begin());
  vector<int> Y = G;
  for (int &v : Y) {
    v = lower_bound(G.begin(), G.end(), v) - G.begin();
  }
  vector<array<int, 2>> C(M);
  for (int i = 0; i < M; i++) {
    C[i][0] = lower_bound(G.begin(), G.end(), X[i][0]) - G.begin();
    C[i][1] = lower_bound(G.begin(), G.end(), X[i][1]) - G.begin();
  }
  vector<int> ord(M);
  iota(ord.begin(), ord.end(), 0);
  sort(ord.begin(), ord.end(), [&](int i, int j) {
    return X[i][0] + X[i][1] < X[j][0] + X[j][1];
  });
  fenwick FA(M), FB(M);
  vector<long long> pref(M + 1);
  long long sum = 0;
  for (int i = 0; i < M; i++) {
    for (int j = 0; j < 2; j++) {
      FA.update(C[ord[i]][j], 1);
      FB.update(C[ord[i]][j], X[ord[i]][j]);
      sum += X[ord[i]][j];
    }
    int Ymed = FA.lower_bound(i + 1);
    int med = G[lower_bound(Y.begin(), Y.end(), Ymed) - Y.begin()];
    int cnt = FA.query(Ymed), Sless = FB.query(Ymed);
    pref[i + 1] = 1LL * med * cnt - Sless + sum - Sless - 1LL * med * ((i + 1) * 2 - cnt);
  }
  vector<long long> suff(M + 1);
  FA = FB = fenwick(M);
  sum = 0;
  for (int i = M - 1; i >= 0; i--) {
    for (int j = 0; j < 2; j++) {
      FA.update(C[ord[i]][j], 1);
      FB.update(C[ord[i]][j], X[ord[i]][j]);
      sum += X[ord[i]][j];
    }
    int Ymed = FA.lower_bound(M - i);
    int med = G[lower_bound(Y.begin(), Y.end(), Ymed) - Y.begin()];
    int cnt = FA.query(Ymed), Sless = FB.query(Ymed);
    suff[i] = 1LL * med * cnt - Sless + sum - Sless - 1LL * med * ((M - i) * 2 - cnt);
  }
  long long res = LLONG_MAX;
  for (int i = 0; i < M; i++) {
    if (i == 0 || K != 1) {
      res = min(res, pref[i] + suff[i]);
    }
  }
  cout << ans + res << "\n";
}

• Subtask 1: 0 / 8
• Subtask 2: 0 / 14
• Subtask 3: 0 / 9
• Subtask 4: 0 / 32
• Subtask 5: 0 / 37