oj.uz

Submission #584010

# Submission time Handle Problem Language Result Execution time Memory
584010 2022-06-26T16:24:24 Z Sam_a17 Link (CEOI06_link) C++14
56 / 100
 1500 ms 34080 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];
  }

  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();

    // dbg(u)

    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) {
    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) {
        answ++, curr = 1;
      }

      for(auto i: adj[u.first]) {
        dist[i] = min(dist[i], curr);
        in[i]--;

        if(!in[i]) {
          used[i] = true;
          q.push({i, dist[i]}); 
        }
      }
    }
  }

  for(int i = 1; i <= n; i++) {
    if(!used[i]) {
      // we get cycle
      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);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
56.0 / 100.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 11988 KB Output isn't correct
2 Execution timed out 1579 ms 11988 KB Time limit exceeded
3 Execution timed out 1592 ms 12116 KB Time limit exceeded
4 Execution timed out 1582 ms 12116 KB Time limit exceeded
5 Execution timed out 1600 ms 12244 KB Time limit exceeded
6 Incorrect 18 ms 13396 KB Output isn't correct
7 Correct 22 ms 14164 KB Output is correct
8 Correct 36 ms 15108 KB Output is correct
9 Correct 41 ms 16596 KB Output is correct
10 Correct 39 ms 16464 KB Output is correct
11 Incorrect 68 ms 19644 KB Output isn't correct
12 Correct 93 ms 20104 KB Output is correct
13 Correct 157 ms 22844 KB Output is correct
14 Correct 162 ms 24872 KB Output is correct
15 Correct 208 ms 27504 KB Output is correct
16 Incorrect 287 ms 29692 KB Output isn't correct
17 Correct 285 ms 31980 KB Output is correct
18 Incorrect 326 ms 33196 KB Output isn't correct
19 Incorrect 345 ms 33364 KB Output isn't correct
20 Correct 332 ms 33244 KB Output is correct
21 Correct 345 ms 33608 KB Output is correct
22 Correct 329 ms 34080 KB Output is correct
23 Incorrect 313 ms 33480 KB Output isn't correct
24 Correct 330 ms 34044 KB Output is correct
25 Correct 344 ms 34012 KB Output is correct