Submission #417702

#	Time	Username	Problem	Language	Result	Execution time	Memory
417702		ioi	Connecting Supertrees (IOI20_supertrees)	C++14	11 / 100	323 ms	30136 KiB

supertrees

#include "supertrees.h"
#include <vector>
#include<bits/stdc++.h>
using namespace std ;
const int N = 1002;
int dsu[N] , sz[N];

int get(int u){
    if(u == dsu[u])
        return u ;

    return dsu[u] = get(dsu[u]);



}

void connect(int u , int v){


    u = get(u) , v = get(v);
    if(u == v)return ;

    if(sz[u] > sz[v])swap(u , v);

    sz[v] += sz[u];

    dsu[u] = v ;



}

bool same(int u , int v){
    u = get(u) , v = get(v);

    return u == v ;

}
vector<int> v , adj[N];

int construct(vector<vector<int>> p) {
	int n = p.size();
	vector<vector<int>> answer (n , vector<int> (n , 0));
    for(int i = 0 ; i < n ; i ++)sz[i] = 1 , dsu[i] = i ;
    int cnt[n] = {} , cnt1[n] = {};

    for(int i = 0 ; i < n ; i ++){
        for(int j = 0 ; j < n ; j ++){
            if(p[i][j])connect(i , j);
            if(i == j)continue;

            cnt[i] += (p[i][j] == 2 );cnt1[i] += (p[i][j] == 1);
            if(p[i][j] == 1 )adj[i].push_back(j) , adj[j].push_back(i);

        }
    }
    map<int, set<int> > mp ;


    for(int i = 0 ; i < n ; i ++){
        for(int j = 0 ; j < n ;j ++)
        {
           // if(p[i][j] == 0&& same(i , j) || (p[i][j] && sz[get(dsu[i])] == 2))return 0 ;
             if(p[i][j] && i != j)mp[dsu[i]].insert(i) , mp[dsu[i]].insert(j);

        }
    }
    int vis[n] = {};

    for(auto f : mp){


         vector<int> els , iif;
            int yes = 0 ;


        int sz = f.second.size();

         for(auto ff : f.second){
            if(cnt[ff] == sz - 1)yes ++ ;
            if(vis[ff] == 0 && cnt[ff]) { iif.push_back(ff);
                for(auto c : adj[ff])vis[c]++;
                vis[ff]++;
            }
            else els.push_back(ff);

         }


         if(iif.size() && yes){
            int past = iif[0];

            for(int i = 1 ; i < iif.size() ; i ++){
                int curr = iif[i];
                answer[curr][past] = answer[past][curr] =1 ;

                past = curr ;
            }
            answer[iif[0]][past] = answer[past][iif[0]] = 1 ;


            for(auto ff : iif){
                v.clear();

                v = adj[ff];
                if(v.size()){
                    int past = ff ;

                    for(int i = 0 ; i < v.size() ; i ++){
                        int curr = v[i];


                        answer[curr][past] = answer[past][curr] = 1 ;
                        past = curr ;

                    }
                }
            }


         }
         else if(!yes || els.size()){



            int past = els[0];
            for(int i = 1 ; i < els.size(); i ++){
                int curr = els[i];

                answer[curr][past] = answer[past][curr] = 1 ;

                past = curr ;

            }
         }



    }


    for(int i = 0 ; i < n ; i ++)answer[i][i] = 0 ;
	build(answer);
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:94:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   94 |             for(int i = 1 ; i < iif.size() ; i ++){
      |                             ~~^~~~~~~~~~~~
supertrees.cpp:110:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  110 |                     for(int i = 0 ; i < v.size() ; i ++){
      |                                     ~~^~~~~~~~~~
supertrees.cpp:128:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  128 |             for(int i = 1 ; i < els.size(); i ++){
      |                             ~~^~~~~~~~~~~~

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