Submission #803638

#	Time	Username	Problem	Language	Result	Execution time	Memory
803638		Warinchai	Connecting Supertrees (IOI20_supertrees)	C++14	0 / 100	1 ms	212 KiB

supertrees

#include "supertrees.h"
#include <vector>
#include<bits/stdc++.h>
using namespace std;
int sz;
vector<vector<int> >v;
vector<vector<int> >ans;
int pr[1005];
int fp(int a){
    if(pr[a]==a){
        return a;
    }
    return pr[a]=fp(pr[a]);
}
void un(int a,int b){
    if(fp(a)!=fp(b)){
        ans[a][b]=1;
        ans[b][a]=1;
        pr[fp(b)]=fp(a);
    }
}
bool build_1(){
    for(int i=0;i<sz;i++){
        for(int j=i+1;j<sz;j++){
            if(v[i][j]==1){
                if(fp(i)!=fp(j)){
                    return 0;
                }
                un(i,j);
            }
        }
    }
    return 1;
}
int use_2[1005];
bool build_2(){
    int count=0;
    vector<int>cy;
    for(int i=0;i<sz;i++){
        for(int j=i+1;j<sz;j++){
            if(v[i][j]==2){
                if(use_2[i]==0){
                    use_2[i]=1;
                    count++;
                    cy.push_back(i);
                }
                if(use_2[j]==0){
                    use_2[j]=1;
                    count++;
                    cy.push_back(j);
                }
                
            }
        }
    }
    if(count<2){
        return 0;
    }
    for(int i=0;i<cy.size()-1;i++){
        un(cy[i],cy[i+1]);
    }
    un(cy[0],cy[cy.size()-1]);
    return 1;
}
bool check_0(){
    for(int i=0;i<sz;i++){
        for(int j=i+1;j<sz;j++){
            if(v[i][j]==0&&fp(i)==fp(j))return 0;
        }
    }
    return 1;
}
int construct(vector<vector<int> > p) {
    //cout<<"work"<<endl;
	sz = p.size();
    bool check=0;
    v.resize(sz);
    for(int i=0;i<sz;i++){
        v[i].resize(sz);
    }
    for(int i=0;i<sz;i++){
        for(int j=0;j<sz;j++){
            //cout<<"i j "<<i<<" "<<j<<endl;
            v[i][j]=p[i][j];
            if(p[i][j]!=p[j][i]||(i==j&&p[i][j]!=1)){
                check=1;
                //cout<<"break"<<endl;
                break;
            }
        }
    }
    //cout<<"work"<<endl;
    if(check){
        return 0;
    }
    //cout<<"work"<<endl;
    ans.resize(sz);
    for(int i=0;i<sz;i++){
        ans[i].resize(sz);
    }
    for(int i=0;i<sz;i++){
        pr[i]=i;
    }
    //cout<<"work"<<endl;
    if(!build_2()){
        return 0;
    }
    if(!build_1()){
        return 0;
    }
    if(!check_0()){
        return 0;
    }else{
        build(ans);
    }
	//cout<<"ans:"<<endl;
	return 1;
}

Compilation message (stderr)

supertrees.cpp: In function 'bool build_2()':
supertrees.cpp:59:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |     for(int i=0;i<cy.size()-1;i++){
      |                 ~^~~~~~~~~~~~

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