Submission #1160160

#	Time	Username	Problem	Language	Result	Execution time	Memory
1160160		jotinha	Bitaro’s Party (JOI18_bitaro)	C++20	0 / 100	2 ms	5704 KiB

bitaro

/**
 *  author:  Jotinha (ツ)
 *  created: 02-28-2025 11:09:44
**/
#include <bits/stdc++.h>

using namespace std;

#ifdef LOCAL
#include "algo/debug.h"
#else
#define debug(...) 42
#endif

vector<pair<int, vector<int>>> qr[100005];
pair<int, int> dp[100005][318];

void countingSort(vector<int>& arr, int mn = 0, int mx = 100000){
  int i, k = 0, sizeTemp = mx - mn + 1;
  vector<int> temp(sizeTemp);
  for(i = 0; i< sizeTemp; i++){
    temp[i] = 0;
  }
  for(i = 0; i < (int) arr.size(); i++){
    temp[arr[i] - mn]++;
  }
  for (i = mx; i >= mn; i--){
    while(temp[i - mn]-- > 0){
      arr[k++] = i;
    }
  }
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, m, q;
  cin >> n >> m >> q;
  vector<vector<int>> g(n);
  for(int i = 0; i < m; i++) {
    int u, v;
    cin >> u >> v;
    --u, --v;
    if(u < v) {
      swap(u, v);
    }
    g[u].push_back(v);
  } 
  vector<int> tot(n);
  int t = 0;
  for(int i = 0; i < q; i++) {
    int u, k;
    cin >> u >> k;
    --u;
    vector<int> v(k);
    for(int& j : v) {
      cin >> j;
      --j;
    }
    qr[u].emplace_back(make_pair(t++, v));
    tot[u] += (int) v.size();
  }
  auto bfs = [&](int u) {
    vector<int> dist(n, -1);
    function<int(int)> dp = [&](int v) {
      int& p = dist[v];
      if(p != -1) {
        return p;
      }
      int ret = 0;
      for(int nxt : g[v]) {
        ret = max(ret, dp(nxt) + 1);
      }
      return p = ret;
    };
    dp(u);
    return dist;
  };
  const int sq = 1;
  const int inf = 0x3f3f3f3f;
  for(int i = 0; i < n; i++) {
    for(int j = 0; j < sq; j++) {
      dp[i][j] = {-inf, -inf};
    }
  }
  vector<int> h(n);
  auto merge = [&](pair<int, int>* a, pair<int, int>* b) {
    pair<int, int> c[sq];
    int at = 0;
    int l = 0, r = 0;
    while(at < sq && l < sq && r < sq) {
      auto [d1, v1] = a[l];
      auto [d2, v2] = b[r];
      d2++;
      if(v1 < 0 or h[v1]) {
        l++;
        continue;
      }
      if(v2 < 0 or h[v2]) {
        r++;
        continue;
      }
      if(v1 >= 0 && d1 > d2) {
        l++;
        h[v1] = 1;
        c[at++] = {d1, v1};
      } else if(v2 >= 0 && !h[v2]){
        r++;
        h[v2] = 1;
        c[at++] = {d2, v2};
      }
    }
    while(at < sq && l < sq) {
      if(a[l].second < 0 or h[a[l].second]) {
        l++;
        continue;
      }
      c[at++] = a[l++];
    }
    while(at < sq && r < sq) {
      if(b[r].second < 0 or h[b[r].second]) {
        r++;
        continue;
      }
      c[at++] = b[r++];
    }
    l = 0;
    while(l < sq) {
      if(a[l].second >= 0) {
        h[a[l].second] = 0;
      }
      if(b[l].second >= 0) {
        h[b[l].second] = 0;
      }
      l++;
    }
    for(int i = 0; i < at; i++) {
      a[i] = c[i];
    }
  };
  vector<int> vis(n);
  function<void(int)> dfs = [&](int u) {
    if(vis[u]) {
      return;
    }
    dp[u][0] = {0, u};
    for(int nxt : g[u]) {
      dfs(nxt);
      merge(dp[u], dp[nxt]);
    }
    vis[u] = 1;
  };
  vector<int> ans(t, -2);
  for(int i = n - 1; i >= 0; i--) {
    if(tot[i] >= sq) {
      auto dist = bfs(i);
      auto d2 = dist;
      for(int j = 0; j < n; j++) {
        d2[j] += 1;
      }
      countingSort(d2);
      for(int j = 0; j < (int) qr[i].size(); j++) {
        sort(qr[i][j].second.begin(), qr[i][j].second.end(), [&](int x, int y) {
          return dist[x] > dist[y];
        });
        int ge = 1;
        for(int k = 0; k < (int) qr[i][j].second.size(); k++) {
          if(dist[qr[i][j].second[k]] != d2[k] - 1) {
            ans[qr[i][j].first] = d2[k] - 1;
            ge = 0;
            break;
          }
        }
        if(ge) {
          if((int) qr[i][j].second.size() == n) {
            ans[qr[i][j].first] = -1;
          } else {
            ans[qr[i][j].first] = d2[(int) qr[i][j].second.size()] - 1;
          }
        }
      }
    } else {
      dfs(i);
      for(int j = 0; j < sq; j++) {
        for(int k = 0; k < (int) qr[i].size(); k++) {
          if(ans[qr[i][k].first] == -2) {
            int show = 1;
            for(int nxt : qr[i][k].second) {
              if(nxt == dp[i][j].second) {
                show = 0;
                break;
              }
            }
            if(show) {
              ans[qr[i][k].first] = dp[i][j].first;
            }
          }
        }
      }
    }
  }
  for(int x : ans) {
    cout << (x < 0 ? -1 : x)  << '\n';
  }
  return 0;
}

• Subtask 1: 0 / 7
• Subtask 2: 0 / 7
• Subtask 3: 0 / 86