Submission #302231

#	Time	Username	Problem	Language	Result	Execution time	Memory
302231		aymane7	Connecting Supertrees (IOI20_supertrees)	C++17	40 / 100	267 ms	22392 KiB

supertrees

#include<bits/stdc++.h>
#include"supertrees.h"
#pragma GCC optimize("O2")
#define S second
#define F first
#define PB push_back
#define sz(x) (int) x.size()
#define all(x) x.begin(),x.end()
#define L(x) 2*x
#define R(x) 2*x+1
#define M(x,y) (x+y)/2
using namespace std;
typedef long long ll;
const int N=1e3+1;
int p[N],lvl[N];
int getp(int x){
    return (p[x]==x)? x : p[x]=getp(p[x]);
}
void unite(int i,int j){
    int x=getp(i),y=getp(j);
    if(x==y)
        return ;
    if(lvl[x]>lvl[y])
        swap(x,y);
    p[x]=y;
    if(lvl[x]==lvl[y])
        lvl[y]++;
}

void build1(vector<vector<int>> t){
    for(auto v:t){
        for(auto x:v)
            cout<<x<<" ";
        cout<<endl;
    }
}
int construct(vector<vector<int>> b){
    int n=sz(b);
    vector<vector<int>> ans(n,vector<int>(n,0));
    vector<int> co[n];
    bool ex2[n]={0};
    for(int i=0;i<n;i++){
        lvl[i]=0;
        p[i]=i;
    }
    for(int i=0;i<n;i++)
        for(int j=0;j<n;j++){
            if(b[i][j]==2)
                unite(i,j),ex2[i]=1;
        }


    for(int i=0;i<n;i++)
        co[getp(i)].PB(i);

    for(int i=0;i<n;i++){
        if(sz(co[i])<=1)
            continue;
        if(sz(co[i])==2){
            return 0;
        }
        for(int j=0;j<sz(co[i])-1;j++)
            ans[co[i][j]][co[i][j+1]]=1,ans[co[i][j+1]][co[i][j]]=1;
        ans[co[i][0]][co[i].back()]=1,ans[co[i].back()][co[i][0]]=1;
        for(auto x:co[i])
        for(auto y:co[i]){
            if(x==y)
                continue;
            if(b[x][y]==0)
                return 0;
        }
    }


    //b[i][j]=1
    for(int i=0;i<n;i++){
        lvl[i]=0;
        p[i]=i;
        co[i].clear();
    }
    for(int i=0;i<n;i++)
        for(int j=0;j<n;j++){
            if(b[i][j]==1)
                unite(i,j);
        }
    for(int i=0;i<n;i++)
        co[getp(i)].PB(i);

    for(int i=0;i<n;i++){
        if(sz(co[i])<=1)
            continue;
        for(int j=0;j<sz(co[i]);j++){
            if(ex2[co[i][j]]){
                swap(co[i][j],co[i][0]);
                break;
            }
        }
        for(int j=0;j<sz(co[i])-1;j++)
            ans[co[i][j]][co[i][j+1]]=1,ans[co[i][j+1]][co[i][j]]=1;
        for(auto x:co[i])
        for(auto y:co[i]){
            if(x==y)
                continue;
            if(b[x][y]==0)
                return 0;
        }
    }

    build(ans);
    return 1;
}
/*
int main(){
    int n;
    cin>>n;
    vector<vector<int>> t(n,vector<int>(n,0));
    for(int i=0;i<n;i++)
        for(int j=0;j<n;j++)
            cin>>t[i][j];
    construct(t);
}
*/

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