Submission #925205

#	Time	Username	Problem	Language	Result	Execution time	Memory
925205		awu	Passport (JOI23_passport)	C++14	0 / 100	1 ms	604 KiB

passport

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

// #define int long long
#define ll long long
// #define double long double
#define all(x) x.begin(), x.end()
#define debug(x) do{auto _x = x; cerr << #x << " = " << _x << endl;} while(0)
#define f first
#define s second
// #define endl '\n'

using pii = pair<int, int>;
using pll = pair<ll, ll>;

const int inf = 1 << 29;
// const ll inf = 1ll << 50;

const int MOD = 1e9 + 7;

signed main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int n; cin >> n;
  int s = 1;
  while(s < n) s *= 2;
  vector<vector<int>> adj(s * 2); // reversed edges
  vector<int> s1, sn;
  for(int i = 0; i < n; i++) {
    int l, r; cin >> l >> r; l--;
    if(l == 0) s1.push_back(i);
    if(r == n) sn.push_back(i);
    auto add = [&](int a, int b) {
      adj[a].push_back(b);
    };
    for(l += s, r += s; l < r; l /= 2, r /= 2) {
      if(l & 1) add(l++, s + i);
      if(r & 1) add(--r, s + i);
    }
  }
  vector<deque<int>> q(n * 4);
  auto dijk = [&](vector<int>& d) {
    int cd = 0;
    while(true) {
      while(cd < q.size() && q[cd].empty()) cd++;
      if(cd == q.size()) break;
      auto cur = q[cd].front(); q[cd].pop_front();
      if(d[cur] <= cd) continue;
      d[cur] = cd;
      for(auto i : adj[cur]) {
        q[cd + 1].push_back(i);
      }
      if(cur > 1) q[cd].push_back(cur / 2);
    }
  };
  for(auto i : s1) {
    q[0].push_back(s + i);
  }
  vector<int> d1(s * 2, inf);
  dijk(d1);
  for(auto i : sn) {
    q[0].push_back(s + i);
  }
  vector<int> dn(s * 2, inf);
  dijk(dn);
  vector<int> d(s * 2, inf);
  for(int i = 0; i < n; i++) {
    int dist = d1[s + i] + dn[s + i];
    if(dist == inf) continue;
    q[dist].push_back(s + i);
  }
  dijk(d);
  int Q; cin >> Q;
  while(Q--) {
    int x; cin >> x; x--;
    cout << (d[s + x] == inf ? -1 : d[s + x] + 1) << endl;
  }
}

Compilation message (stderr)

passport.cpp: In lambda function:
passport.cpp:46:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::deque<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |       while(cd < q.size() && q[cd].empty()) cd++;
      |             ~~~^~~~~~~~~~
passport.cpp:47:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::deque<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |       if(cd == q.size()) break;
      |          ~~~^~~~~~~~~~~

• Subtask 1: 0 / 6
• Subtask 2: 0 / 16
• Subtask 3: 0 / 24
• Subtask 4: 0 / 8
• Subtask 5: 0 / 46