Submission #441995

#	Time	Username	Problem	Language	Result	Execution time	Memory
441995		julian33	Connecting Supertrees (IOI20_supertrees)	C++14	96 / 100	257 ms	28056 KiB

supertrees

#include <bits/stdc++.h>
#include "supertrees.h"

using namespace std;

#ifdef LOCAL
#define deb(...) logger(#__VA_ARGS__, __VA_ARGS__)
template<typename ...Args>
void logger(string vars, Args&&... values) {
    cerr<<vars<<" = ";
    string delim="";
    (...,(cerr<<delim<<values,delim=", "));
    cerr<<"\n";
}
#else
#define deb(...) logger(#__VA_ARGS__, __VA_ARGS__)
template<typename ...Args>
void logger(string vars, Args&&... values) {}
#endif

#define FOR(i,j,n) for(int i=j;i<n;i++)

#define pb push_back
#define sz(x) (int)(x.size())
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
template<typename T> inline void maxa(T& a,T b){a=max(a,b);}
template<typename T> inline void mina(T& a,T b){a=min(a,b);} 

// void build(vector<vector<int>> b){
//     int n=sz(b); 
//     for(int i=0;i<n;i++){
//         for(int j=0;j<n;j++){
//             cout<<b[i][j]<<" ";
//         }
//         cout<<"\n";
//     }
// }

const int mxN=1e3+5;

int uf[mxN],seen[mxN];
vector<int> component[mxN];
vector<vector<int>> g;

int find(int x){return uf[x]<0?x:uf[x]=find(uf[x]);}
bool same(int x,int y){return find(x)==find(y);}
void unite(int x,int y){
    x=find(x); y=find(y);
    if(x==y)
        return;
    if(uf[x]>uf[y])
        swap(x,y);
    uf[x]+=uf[y]; uf[y]=x;
}

int construct(vector<vector<int>> p){
    g=p;
    memset(uf,-1,sizeof(uf));
    int n=sz(p);
    vector<vector<int>> b;
    b.resize(n);
    for(auto &u:b)
        u.resize(n);
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
            if(g[i][j]){
                unite(i,j);
            }
        }
    }
    for(int i=0;i<n;i++){
        component[find(i)].pb(i);
        for(int j=0;j<n;j++){
            if(!g[i][j] && same(i,j))
                return 0;
        }
    }
    for(int i=0;i<n;i++){
        //u pretty much have one line graph and one ring
        if(sz(component[i])<=1)
            continue;
        vector<vector<int>> line; vector<int> ring;
        for(int &j:component[i]){
            if(seen[j])
                continue;
            vector<int> one={j};
            for(int k=0;k<n;k++){
                if(g[j][k]==1 && j!=k){
                    one.pb(k);
                    seen[k]=1;
                }
            }
            if(sz(one)==1)
                ring.pb(j);
            else
                line.pb(one);
        }
        if(sz(line)==0){
            if(sz(ring)==2)
                return 0;
            for(int j=0;j<sz(ring);j++){
                b[ring[j]][ring[(j+1)%sz(ring)]]=b[ring[(j+1)%sz(ring)]][ring[j]]=1;
            }
        } else{
            for(int j=0;j<sz(ring)-1;j++){
                b[ring[j]][ring[j+1]]=b[ring[j+1]][ring[j]]=1;
            }
            for(auto u:line){
                for(int j=0;j<sz(u)-1;j++){
                    b[u[j]][u[j+1]]=b[u[j+1]][u[j]]=1;
                }
            }
            for(int j=0;j<sz(line)-1;j++){
                b[line[j][0]][line[j+1][0]]=b[line[j+1][0]][line[j][0]]=1;
            }
            if(sz(ring)){
                b[line.back()[0]][ring.back()]=b[ring.back()][line.back()[0]]=1;
                b[line[0][0]][ring[0]]=b[ring[0]][line[0][0]]=1;
            } else if(sz(line)>1){
                b[line.back()[0]][line[0][0]]=b[line[0][0]][line.back()[0]]=1;
            }
        }
    }
    build(b);
    return 1;
}

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