Submission #584029

# Submission time Handle Problem Language Result Execution time Memory
584029 2022-06-26T16:56:38 Z Sam_a17 Link (CEOI06_link) C++14
0 / 100
356 ms 34328 KB
#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
//#include "temp.cpp"
#include <cstdio>
using namespace std;

#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif

#define sz(x) (int((x).size()))
#define len(x) (int)x.length()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define clr(x) (x).clear()
#define uniq(x) x.resize(unique(all(x)) - x.begin());
#define blt __builtin_popcount

#define pb push_back
#define popf pop_front
#define popb pop_back
#define ld long double
#define ll long long

void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
void print(long double t) {cerr << t;}

template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T> void print(T v[],T n) {cerr << "["; for(int i = 0; i < n; i++) {cerr << v[i] << " ";} cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}

#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define nl '\n'

// for grid problems
int dx[8] = {-1,0,1,0,1,-1,1,-1};
int dy[8] = {0,1,0,-1,1,1,-1,-1};

// lowest / (1 << 17) >= 1e5 / (1 << 18) >= 2e5 / (1 << 21) >= 1e6
void fastIO() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr); cout.tie(nullptr);
}
// file in/out
void setIO(string str = "") {
  fastIO();

  if (str != "") {
    freopen((str + ".in").c_str(), "r", stdin);
    freopen((str + ".out").c_str(), "w", stdout);
  }
}

// Indexed Set
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
const int N = 5e5 + 10, inf = 1e9;
int n, k, in[N], dist[N], answ;
vector<int> adj[N];
bool used[N];

int cycle(int node) {
  // dbg(node)
  int cur = node;
  vector<int> path;
  while(!used[cur]) {
    used[cur] = true;
    path.push_back(cur);
    cur = adj[cur][0];
  }

  // dbg(path)

  // dbg(sz(path))

  for(auto i: path) {
    used[i] = false;
  }

  {
    priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>> > q;

    for(auto i: path) {
      q.push({dist[i], i});
    }

    while(!q.empty()) {
      auto u = q.top();
      q.pop();
      if(used[u.second]) {
        continue;
      }
      used[u.second] = true;

      if(u.first >= k) {
        break;
      }

      for(auto i: adj[u.second]) {
        if(dist[i] > dist[u.second] + 1) {
          dist[i] = dist[u.second] + 1;
          q.push({dist[i], i});
        }
      }
    }
  }
  
  int m = sz(path);

  int mini = 0;
  for(int i = 0; i < m; i++) {
    if(dist[path[i]] == inf) {
      ++mini;
    }
  }

  if(!mini) {
    for(auto i: path) {
      used[i] = true;
    }
    return 0;
  }

  int lst = -1;
  vector<int> ptr(m, 0);
  for(int i = 2 * m - 1; i >= 0; i--) {
    if(dist[path[i % m]] == inf) {
      lst = i % m;
      ptr[lst] = lst;
    } else if(lst != -1) {
      ptr[i % m] = lst;
    }
  }

  for(int start = 0; start < min(k, m); start++) {
    int road = 0, pos = start, ansi = 0;
    while(true) {
      road += ptr[pos] - pos;
      pos = ptr[pos];
      
      if(road >= m) {
        break;
      }

      ansi++, road += k;
      pos += k, pos %= m;
    }

    mini = min(mini, ansi);
  }

  //
  for(auto i: path) {
    used[i] = true;
  }

  return mini;
}

void solve_() {
  cin >> n >> k;
  for(int i = 1; i <= n; i++) {
    int a, b; cin >> a >> b;
    adj[a].push_back(b); in[b]++;
  }

  for(int i = 2; i <= n; i++) {
    if(!in[i]) {
      adj[1].push_back(i);
      in[i]++;
      answ++;
    }
  }

  {
    for(int i = 1; i <= n; i++) {
      dist[i] = inf;
    }

    queue<pair<int, int>> q;
    q.push({1, 0});
    used[1] = true;

    while(!q.empty()) {
      auto u = q.front();
      q.pop();

      // dbg(u)
      int curr = u.second + 1;
      if(curr > k) {
        curr = 1;
      }

      for(auto i: adj[u.first]) {
        if(dist[i] > curr) {
          dist[i] = curr;
          if(!in[i] && !used[i]) {
            used[i] = true;
            q.push({i, dist[i]}); 
          }
        }
        
        in[i]--;
      }
    }
  }

  dbg(answ)

  for(int i = 1; i <= n; i++) {
    if(!used[i]) {
      answ += cycle(i);
    }
  }


  printf("%d\n", answ);
}

int main () {
  setIO("");

  auto solve = [&](int test_case)-> void {
    while(test_case--) {
      solve_();
    }
  };

  int test_cases = 1;
  solve(test_cases);

  return 0;
}

Compilation message

link.cpp: In function 'void setIO(std::string)':
link.cpp:65:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   65 |     freopen((str + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
link.cpp:66:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   66 |     freopen((str + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 11988 KB Output isn't correct
2 Incorrect 6 ms 11988 KB Output isn't correct
3 Incorrect 6 ms 12080 KB Output isn't correct
4 Incorrect 9 ms 12116 KB Output isn't correct
5 Incorrect 8 ms 12244 KB Output isn't correct
6 Incorrect 24 ms 13320 KB Output isn't correct
7 Incorrect 30 ms 14208 KB Output isn't correct
8 Incorrect 28 ms 15060 KB Output isn't correct
9 Incorrect 45 ms 16680 KB Output isn't correct
10 Incorrect 45 ms 16568 KB Output isn't correct
11 Incorrect 71 ms 19744 KB Output isn't correct
12 Incorrect 103 ms 20228 KB Output isn't correct
13 Incorrect 189 ms 23016 KB Output isn't correct
14 Incorrect 187 ms 24960 KB Output isn't correct
15 Incorrect 213 ms 27568 KB Output isn't correct
16 Incorrect 290 ms 29624 KB Output isn't correct
17 Incorrect 340 ms 31992 KB Output isn't correct
18 Incorrect 356 ms 33232 KB Output isn't correct
19 Incorrect 335 ms 33320 KB Output isn't correct
20 Incorrect 338 ms 33340 KB Output isn't correct
21 Incorrect 348 ms 33980 KB Output isn't correct
22 Incorrect 321 ms 33680 KB Output isn't correct
23 Incorrect 323 ms 33528 KB Output isn't correct
24 Incorrect 339 ms 34328 KB Output isn't correct
25 Incorrect 330 ms 34252 KB Output isn't correct