Submission #1222471

#	Time	Username	Problem	Language	Result	Execution time	Memory
1222471		hmms127	슈퍼트리 잇기 (IOI20_supertrees)	C++20	100 / 100	121 ms	22260 KiB

supertrees

#include "supertrees.h"
#include <vector>
using namespace std;
#define pb push_back
struct DSU{
  vector<int>par,sz;
  void init(int n){
      par.resize(n+1);sz.resize(n+1);
      for(int i=0;i<n;i++)par[i]=i,sz[i]=1;
  }  
  int root(int u){
      return par[u]==u ? u:par[u]=root(par[u]);
  }
  bool merge(int u,int v){
      int ru=root(u),rv=root(v);
      if(ru==rv)return 0;
      if(sz[ru]>sz[rv])swap(sz[ru],sz[rv]);
      par[ru]=rv;sz[rv]+=sz[ru];
      return 1;
  }
};

int construct(std::vector<std::vector<int>> p) {
	int n=p[0].size();
    vector<vector<int>>v(n,vector<int>(n,0));
    DSU d1,d2;d1.init(n);d2.init(n);
    for(int i=0;i<n;i++){
        for(int j=i+1;j<n;j++){
            if(p[i][j]==0)continue;
            if(p[i][j]==3)return 0;
            d1.merge(i,j);
        }
    }
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
            if(p[i][j]==0&&d1.root(i)==d1.root(j))return 0;
        }
    }
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
            if(p[i][j]==1)d2.merge(i,j);
        }
    }
    vector<vector<int>>comp(n),comp1(n);
    for(int i=0;i<n;i++){
        comp[d2.root(i)].pb(i);
        if(d2.root(i)==i)comp1[d1.root(i)].pb(i);
    }
    for(int i=0;i<n;i++){
      if(d2.root(i)==i){
        for(int j=1;j<comp[i].size();j++){
          v[comp[i][j-1]][comp[i][j]]=1;v[comp[i][j]][comp[i][j-1]]=1;
        }
      }
    }
    for(int i=0;i<n;i++){
        if(d1.root(i)!=i)continue;
        if(comp1[i].size()==2)return 0;
        if(comp1[i].size()>1){
          for(int j=0;j<comp1[i].size();j++){
              int u=comp1[i][j],v1=comp1[i][(j+1)%comp1[i].size()];
              v[u][v1]=1;v[v1][u]=1;
          }
        }
        for(int j=0;j<comp1[i].size();j++){
            for(int k=0;k<comp[comp1[i][j]].size();k++){
                for(int l=0;l<n;l++){
                    if(d1.root(l)==i && d2.root(l)!=comp1[i][j]){
                      if(p[comp[comp1[i][j]][k]][l]!=2)return 0;
                    }
                }
            }
        }

        
    }
	build(v);
	return 1;
}

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