Submission #712758

#	Time	Username	Problem	Language	Result	Execution time	Memory
712758		acm	Bridges (APIO19_bridges)	C++17	100 / 100	2187 ms	12068 KiB

bridges

#ifdef ONLINE_JUDGE
#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,O3")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#endif
#include <bits/stdc++.h>
#define speed                   \
  ios_base::sync_with_stdio(0); \
  cin.tie(0);                   \
  cout.tie(0);
#define precision     \
  cout.precision(30); \
  cerr.precision(10);
#define ll long long
#define ld long double
#define pb(x) push_back(x)
#define sz(x) (int)x.size()
#define mp(x, y) make_pair(x, y)
#define all(x) x.begin(), x.end()
#define pc(x) __builtin_popcount(x)
#define pcll(x) __builtin_popcountll(x)
#define F first
#define S second
using namespace std;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
void ioi(string name) {
  freopen((name + ".in").c_str(), "r", stdin);
  freopen((name + ".out").c_str(), "w", stdout);
}
const int bl = 1000;
int n, m, q, p[100005], sz[100005], a[100005], b[100005], c[100005],
    type[100005], X[100005], Y[100005], w[100005], res[100005];
vector<int> stk, upd[100005];
int get(int v) {
  while (v != p[v]) v = p[v];
  return v;
}
void unt(int u, int v) {
  if ((u = get(u)) == (v = get(v))) return;
  if (sz[u] < sz[v]) swap(u, v);
  sz[u] += sz[v], p[v] = u;
  stk.pb(v);
}
void roll(int old_sz) {
  while (sz(stk) > old_sz) {
    int v = stk.back();
    stk.pop_back();
    sz[p[v]] -= sz[v], p[v] = v;
  }
}
int main() {
  speed;
  precision;
  // code
  cin >> n >> m;
  for (int i = 1; i <= m; i++) cin >> a[i] >> b[i] >> c[i];
  cin >> q;
  for (int I = 1, h = 1; I <= q; I++, h++) {
    cin >> type[h] >> X[h] >> Y[h];
    if (!(h % bl) || I == q) {
      stk.clear();
      for (int i = 1; i <= n; i++) sz[i] = 1, p[i] = i;
      for (int i = 1; i <= m; i++) upd[i].clear(), w[i] = 0;
      for (int i = 1; i <= h; i++)
        if (type[i] == 1) upd[X[i]].pb(i), w[X[i]] = 1;
      vector<pair<int, int>> edge;
      vector<int> later;
      for (int i = 1; i <= m; i++) {
        if (!w[i])
          edge.pb(mp(c[i], i));
        else
          later.pb(i);
      }
      sort(all(edge));
      vector<pair<pair<int, int>, int>> ask;
      for (int i = 1; i <= h; i++)
        if (type[i] == 2) ask.pb(mp(mp(Y[i], i), X[i]));
      sort(all(ask));
      for (int i = sz(ask) - 1, j = sz(edge) - 1; i >= 0; i--) {
        while (j >= 0 && ask[i].F.F <= edge[j].F) {
          unt(a[edge[j].S], b[edge[j].S]);
          j--;
        }
        int old_sz = sz(stk);
        for (auto k : later) {
          int kek = c[k];
          for (auto to : upd[k]) {
            if (to > ask[i].F.S) break;
            kek = Y[to];
          }
          if (ask[i].F.F <= kek) unt(a[k], b[k]);
        }
        res[ask[i].F.S] = sz[get(ask[i].S)];
        roll(old_sz);
      }
      for (int i = 1; i <= h; i++)
        if (type[i] == 1) c[X[i]] = Y[i];
      for (int i = 1; i <= h; i++)
        if (type[i] == 2) cout << res[i] << "\n";
      h = 0;
    }
  }
  // endl
#ifndef ONLINE_JUDGE
  cerr << "\nTime elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
#endif
  return 0;
}

Compilation message (stderr)

bridges.cpp: In function 'void ioi(std::string)':
bridges.cpp:26:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |   freopen((name + ".in").c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bridges.cpp:27:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |   freopen((name + ".out").c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 16 / 16
• Subtask 3: 17 / 17
• Subtask 4: 14 / 14
• Subtask 5: 13 / 13
• Subtask 6: 27 / 27