Submission #243942

#	Time	Username	Problem	Language	Result	Execution time	Memory
243942		fedoseevtimofey	Selling RNA Strands (JOI16_selling_rna)	C++14	100 / 100	162 ms	79512 KiB

selling_rna

#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <deque>
#include <stack>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <cstring>
#include <cmath>
#include <cstdlib>
#include <algorithm>
#include <random>
#include <iomanip>
#include <functional>
#include <cassert>

using namespace std;

typedef long long ll;

const int L = 4e6 + 7;

string rev(string s) {
  reverse(s.begin(), s.end());
  return s;
} 

int get_id(char c) {
  if (c == 'A') {
    return 0;
  } else if (c == 'G') {
    return 1;
  } else if (c == 'C') {
    return 2;
  } else {
    return 3;
  }
}

int go[L][4];
int l[L], r[L];

int uk = 2;

int add(string s, int rt) {
  int v = rt;
  for (char c : s) {
    int id = get_id(c);
    if (go[v][id] == 0) {
      go[v][id] = uk++;
    }
    v = go[v][id];
  }
  return v;
}

int find_string(string s, int rt) {
  int v = rt;
  for (char c : s) {
    int id = get_id(c);
    if (go[v][id] == 0) return -1;
    v = go[v][id];
  }
  return v;
}

vector <int> e;

void dfs(int u) {
  e.push_back(u);
  l[u] = (int)e.size() - 1;
  for (int i = 0; i < 4; ++i) {
    if (go[u][i] != 0) {
      dfs(go[u][i]);
    }
  }
  r[u] = (int)e.size() - 1;
}

struct Fenwick {
  vector <int> f;
  int n;
  Fenwick(int nn) {
    n = nn;
    f.resize(n);
  }
  void modify(int i, int val) {
    for (; i < n; i |= i + 1) {
      f[i] += val;
    }
  }

  int get(int r) {
    int res = 0;
    for (; r >= 0; r &= r + 1, --r) {
      res += f[r];
    }
    return res;
  }

  int sum(int l, int r) {
    return get(r) - get(l - 1);
  }
};

struct Event {
  int x, l, r, tp, id;
  Event(int x, int l, int r, int tp, int id) : x(x), l(l), r(r), tp(tp), id(id) {}
  bool operator <(const Event &other) const {
    if (x != other.x) return x < other.x;
    return id < other.id;
  }
};    

int main() {
  ios_base::sync_with_stdio(false); cin.tie(0);
#ifdef LOCAL
  freopen("input.txt", "r", stdin);
#endif
  int n, m;
  cin >> n >> m;
  int rt1 = 0, rt2 = 1;
  vector <vector <int>> where(2, vector <int> (n));
  for (int i = 0; i < n; ++i) {
    string s;
    cin >> s;
    where[0][i] = add(s, rt1);
    where[1][i] = add(rev(s), rt2);
  }

  dfs(rt1); 
  e.clear();
  dfs(rt2);
  vector <Event> events;
  for (int i = 0; i < n; ++i) {
    events.emplace_back(l[where[0][i]], l[where[1][i]], -1, -1, -1);
  }
  vector <int> ans(m); 
  for (int i = 0; i < m; ++i) {
    string p, q;
    cin >> p >> q;
    q = rev(q);
    int s1 = find_string(p, rt1), s2 = find_string(q, rt2);
    if (s1 == -1 || s2 == -1) {
      continue;
    }
    events.emplace_back(r[s1], l[s2], r[s2], 1, i);
    events.emplace_back(l[s1] - 1, l[s2], r[s2], -1, i);
  } 
  sort(events.begin(), events.end());
  Fenwick F(L);
  for (auto e : events) {
    if (e.id == -1) {
      F.modify(e.l, 1);
    } else {
      ans[e.id] += e.tp * F.sum(e.l, e.r);
    }   
  } 
  for (int i = 0; i < m; ++i) {
    cout << ans[i] << '\n';
  }
}

• Subtask 1: 10 / 10
• Subtask 2: 25 / 25
• Subtask 3: 25 / 25
• Subtask 4: 40 / 40