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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#457203#2214. Link Cut Digraphhos_lyricWA 269ms52924kbC++144.3kb2024-06-29 09:03:412024-06-29 09:03:42

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你现在查看的是最新测评结果

  • [2024-06-29 09:03:42]
  • 评测
  • 测评结果:WA
  • 用时:269ms
  • 内存:52924kb
  • [2024-06-29 09:03:41]
  • 提交

answer

#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <functional>
#include <iostream>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

using Int = long long;

template <class T1, class T2> ostream &operator<<(ostream &os, const pair<T1, T2> &a) { return os << "(" << a.first << ", " << a.second << ")"; };
template <class T> ostream &operator<<(ostream &os, const vector<T> &as) { const int sz = as.size(); os << "["; for (int i = 0; i < sz; ++i) { if (i >= 256) { os << ", ..."; break; } if (i > 0) { os << ", "; } os << as[i]; } return os << "]"; }
template <class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cerr << *i << " "; cerr << endl; }
template <class T> bool chmin(T &t, const T &f) { if (t > f) { t = f; return true; } return false; }
template <class T> bool chmax(T &t, const T &f) { if (t < f) { t = f; return true; } return false; }
#define COLOR(s) ("\x1b[" s "m")


vector<int> uf;
int root(int u) {
  return (uf[u] < 0) ? u : (uf[u] = root(uf[u]));
}
bool connect(int u, int v) {
  u = root(u);
  v = root(v);
  if (u == v) return false;
  if (uf[u] > uf[v]) swap(u, v);
  uf[u] += uf[v];
  uf[v] = u;
  return true;
}


namespace scc {
int n, l;
vector<vector<int>> graph, hparg;
vector<int> ids;
vector<int> stack;
void init(int n_) {
  n = n_;
  graph.assign(n, {});
  hparg.assign(n, {});
  ids.assign(n, -2);
  stack.clear();
}
void clear(int u) {
  graph[u].clear();
  hparg[u].clear();
  ids[u] = -2;
}
void ae(int u, int v) {
  graph[u].push_back(v);
  hparg[v].push_back(u);
}
void dfs0(int u) {
  if (ids[u] == -2) {
    ids[u] = -1;
    for (const int v : graph[u]) dfs0(v);
    stack.push_back(u);
  }
}
void dfs1(int u) {
  if (ids[u] == -1) {
    ids[u] = l;
    for (const int v : hparg[u]) dfs1(v);
  }
}
void run1() {
  l = 0;
  for (; stack.size(); ) {
    const int u = stack.back();
    stack.pop_back();
    if (ids[u] == -1) {
      dfs1(u);
      ++l;
    }
  }
}
}  // scc


int N, M;
vector<int> A, B;

// connect iss[i][*] when adding edge i
vector<vector<int>> iss;

using Edge = pair<pair<int, int>, int>;
void rec(int l, int r, const vector<Edge> &es) {
// cerr<<"[rec] "<<l<<" "<<r<<" "<<es<<endl;
  if (l + 1 == r) {
    for (const Edge &e : es) {
      iss[l].push_back(e.second);
    }
  } else {
    const int mid = (l + r) / 2;
    for (const Edge &e : es) {
      const int u = e.first.first, v = e.first.second;
      scc::clear(u);
      scc::clear(v);
    }
    for (const Edge &e : es) if (e.second < mid) {
      const int u = e.first.first, v = e.first.second;
      scc::ae(u, v);
    }
    for (const Edge &e : es) {
      const int u = e.first.first, v = e.first.second;
      scc::dfs0(u);
      scc::dfs0(v);
    }
    scc::run1();
    vector<Edge> esL, esR;
    for (const Edge &e : es) {
      const int u = e.first.first, v = e.first.second;
      if (scc::ids[u] == scc::ids[v]) {
        esL.emplace_back(make_pair(u, v), e.second);
      } else {
        esR.emplace_back(make_pair(scc::ids[u], scc::ids[v]), e.second);
      }
    }
    rec(l, mid, esL);
    rec(mid, r, esR);
  }
}

Int c2(Int n) {
  return n * (n - 1) / 2;
}

int main() {
  for (; ~scanf("%d%d", &N, &M); ) {
    A.resize(M);
    B.resize(M);
    for (int i = 0; i < M; ++i) {
      scanf("%d%d", &A[i], &B[i]);
      --A[i];
      --B[i];
    }
    
    scc::init(N);
    vector<Edge> es(M);
    for (int i = 0; i < M; ++i) {
      es[i] = Edge(make_pair(A[i], B[i]), i);
    }
    iss.assign(M, {});
    rec(0, M, es);
// cerr<<"iss = "<<iss<<endl;
    
    uf.assign(N, -1);
    Int now = 0;
    for (int i = 0; i < M; ++i) {
      for (const int j : iss[i]) {
        const int u = root(A[j]);
        const int v = root(B[j]);
        if (u != v) {
          now -= c2(-uf[u]);
          now -= c2(-uf[v]);
          connect(u, v);
          now += c2(-uf[root(u)]);
        }
      }
      printf("%lld\n", now);
    }
  }
  return 0;
}

Details

Test #1:

score: 0
Wrong Answer
time: 269ms
memory: 52924kb