Submission #603788

#	Time	Username	Problem	Language	Result	Execution time	Memory
603788		Sam_a17	Connecting Supertrees (IOI20_supertrees)	C++14	40 / 100	268 ms	36424 KiB

supertrees

// #include "A.cpp"
#include <bits/stdc++.h>
// #include <vector>
using namespace std;
 
#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 dbg(x) cout << #x << " " << x << endl;
#define uniq(x) x.resize(unique(all(x)) - x.begin());
 
#define pb push_back
#define ld long double
#define ll long long
 
void build(std::vector<std::vector<int>> p);
 
const int N = 2e5 + 10, M = 1e3 + 10;
int par[N], sz[N], arden[N];
set<int> st[N];
bitset<M> biti[M];
vector<int> adj[N];

int find(int a) {
  if(a != par[a]) {
    par[a] = find(par[a]);
  }
  return par[a];
}
 
int same(int a, int b) {
  if(find(a) == find(b)) {
    return 1;
  } else {
    return 0;
  }
}
 
int merge(int a, int b) {
  a = find(a), b = find(b);
  if(a == b) {
    return 0;
  }
 
  if(sz[a] < sz[b]) {
    swap(a, b);
  }
 
  par[b] = a, sz[a] += sz[b];
  for(auto i: st[b]) {
    st[a].insert(i);
  } st[b].clear();
  return 1;
}
 
int construct(std::vector<std::vector<int>> p) {
	int n = p.size();
	bool allOne = true, lowerOne = true, zeroOrtwo = true;
  for(int i = 0; i < n; i++) {
    for(int j = 0; j < n; j++) {
      if(p[i][j] == 3) {
        return 0;
      }

      if(p[i][j] != 1) {
        allOne = false;
      }
 
      if(p[i][j] > 1) {
        lowerOne = false;
      }
 
      if(i == j) continue;
      if(p[i][j] == 1 || p[i][j] == 3) {
        zeroOrtwo = false;
      }
    }
  }
 
  for(int i = 0; i < n; i++) {
    for(int j = 0; j < n; j++) {
      if(p[i][j] != p[j][i]) {
        return 0;
      }
    }
  }
 
  if(allOne) {
    vector<vector<int>> answ(n, vector<int> (n, 0));
    for(int i = 0; i < n - 1; i++){
      answ[i][i + 1] = 1;
      answ[i + 1][i] = 1;
    }
	  build(answ);
    return 1;
  }
 
  if(lowerOne) {
    vector<vector<int>> answ(n, vector<int> (n, 0));
    
    for(int i = 0; i < n; i++) {
      par[i] = i, sz[i] = 1;
    }
    
    for(int i = 0; i < n; i++) {
      for(int j = 0; j < n; j++) {
        if(p[i][j] == 1) {
          if(merge(i, j)) {
            answ[i][j] = answ[j][i] = 1;
          }
        }
      }
    }
 
 
    for(int i = 0; i < n; i++) {
      for(int j = 0; j < n; j++) {
        if(same(i, j) != p[i][j]) {
          return 0;
        }
      }
    }
 
	  build(answ);
    return 1;
  }
 
  if(zeroOrtwo){
    vector<vector<int>> answ(n, vector<int> (n, 0));
    for(int i = 0; i < n; i++) {
      par[i] = i, sz[i] = 1;
      st[i].insert(i);
    }
    
    for(int i = 0; i < n; i++) {
      for(int j = 0; j < n; j++) {
        if(p[i][j]) biti[i][j] = 1;
      }
    }
 
    // vector<int> out(n, 0);
    vector<int> ans, vis(n);
    vector<vector<int>> components;
    for(int i = 0; i < n; i++) {
      if(vis[i]) continue;
      // dbg(i)
 
      for(int j = 0; j < n; j++) {
        if(p[i][j] == 2) {
          // dbg(j) 
          merge(i, j);
        }
      }
 
      int pa = find(i);
 
      // const int x = n;
      bitset<M> bt;
 
      for(auto j: st[pa]) {
        bt[j] = 1;
      }
 
      // cout << bt << endl;
 
      for(auto j: st[pa]) {
        if((biti[j] | bt) != bt || (biti[j] & bt) != bt) {
          return 0;
        }
      }
 
      if(sz(st[pa]) == 2) {
        return 0;
      }
 
      vector<int> comp;
      for(auto j: st[pa]) {
        vis[j] = true;
        comp.push_back(j);
      }
 
      components.push_back(comp);
    }
 
    for(auto i: components) {
      for(int j = 1; j < sz(i); j++) {
        answ[i[j]][i[j - 1]] = 1;
        answ[i[j - 1]][i[j]] = 1;
      }
 
      answ[i.back()][i.front()] = 1;
      answ[i.front()][i.back()] = 1;
    }

    // if(n > 7) {
    //   answ[4][4] = 0;
    //   answ[7][7] = 0;
    // }
    for(int i = 0; i < n; i++) {
      answ[i][i] = 0;
    }

    build(answ);
    return 1;
  }


  vector<vector<int>> answ(n, vector<int> (n, 0));
  vector<int> cont;

  {
    vector<int> vis(n);
    for(int i = 0; i < n; i++) {
      if(vis[i]) continue;

      vis[i] = 1;
      vector<int> merged{i};
      for(int j = 0; j < n; j++) {
        if(!vis[j] && i != j && p[i][j] == 1) {
          answ[i][j] = answ[j][i] = 1;
          vis[j] = 1;
          merged.push_back(j);
        }
      }

      if(sz(merged) >= 2) {
        int back = merged.back();
        cont.push_back(back);
        arden[back] = 1;
        merged.pop_back();
        for(auto j: merged) {
          arden[j] = 1;
          adj[back].push_back(j);
        }
      }
    }
  }

  // gtnenq ciklery merge anenq irar
  // taky mnac gcery

  {
    vector<bool> vis(n);
    for(auto i: cont) {
      if(vis[i]) continue;
      vis[i] = true;
      int lst = i;
      for(int j = 0; j < n; j++) {
        if(p[i][j] == 2) {
          vis[j] = true;
          answ[lst][j] = answ[j][lst] = 1;
          lst = j;
        }
      }
    }
  }

  for(int i = 0; i < n; i++) {
    if(adj[i].empty()) continue;
    for(auto j: adj[i]) {
      answ[i][j] = answ[j][i] = 1;
    }
  }

  for(int i = 0; i < n; i++) {
    answ[i][i] = 0;
  }
  build(answ);

	return 1;
}

• Subtask 1: 11 / 11
• Subtask 2: 10 / 10
• Subtask 3: 19 / 19
• Subtask 4: 0 / 35
• Subtask 5: 0 / 21
• Subtask 6: 0 / 4