Submission #1084266

#	Time	Username	Problem	Language	Result	Execution time	Memory
1084266		Tymond	Connecting Supertrees (IOI20_supertrees)	C++17	21 / 100	195 ms	32068 KiB

supertrees

#include <bits/stdc++.h>
#include "supertrees.h"
using namespace std;
using ll = long long;
using ld = long double;
#define fi first
#define se second
#define vi vector<int>
#define vll vector<long long>
#define pii pair<int, int>
#define pll pair<long long, long long>
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng64(chrono::steady_clock::now().time_since_epoch().count());
inline int rand(int l,int r){return uniform_int_distribution<int>(l, r)(rng);}
inline ll rand(ll l,ll r){return uniform_int_distribution<ll>(l, r)(rng64);}
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

const int MAXN = 1e3 + 7;
int vis[MAXN];
int p[MAXN][MAXN];
vi g[MAXN];
int n;
vector<vi> ans;

vi akt;
map<int, int> cnt;
void getOthers(int v){
    queue<int> q;
    q.push(v);
    vis[v] = 1;
    while(sz(q)){
        v = q.front();
        q.pop();

        cnt[v] = 1;
        akt.pb(v);
        for(auto u : g[v]){
            if(!vis[u]){
                vis[u] = 1;
                q.push(u);
            }
        }
    }
}

/*void build(vector<vi> xd){
    for(int i = 0; i < sz(xd); i++){
        for(auto ele : xd[i]){
            cout << ele << ' ';
        }
        cout << '\n';
    }
}*/

int construct(vector<vi> given) {
    n = sz(given);
    ans.resize(n);
    for(int i = 0; i < n; i++){
        ans[i].assign(n, 0);
        for(int j = 0; j < n; j++){
            p[i][j] = given[i][j];
            if(p[i][j] > 0 && i != j){
                g[i].pb(j);
            }
        }
    }

    for(int i = 0; i < n; i++){
        if(!vis[i]){
            akt.clear();
            cnt.clear();
            getOthers(i);

            int mx = 0;
            for(auto ele : akt){
                for(int x = 0; x < n; x++){
                    if(x != ele && p[ele][x] == 0 && cnt[x]){
                        return 0;
                    }
                    if(cnt[x]){
                        mx = max(mx, p[ele][x]);
                    }
                }
            }

            if(mx == 1){
                for(int x = 0; x < sz(akt) - 1; x++){
                    ans[akt[x]][akt[x + 1]] = 1;
                    ans[akt[x + 1]][akt[x]] = 1;
                }
                continue;
            }

            map<int, int> f;
            vector<vi> groups;
            int k = 0;
            for(auto ele : akt){
                if(f[ele]){
                    continue;
                }
                groups.pb({ele});
                queue<int> q;
                q.push(ele);
                f[ele] = 1;
                while(sz(q)){
                    int v = q.front();
                    q.pop();

                    for(auto u : g[v]){
                        if(u != v && !f[u] && p[ele][u] == 1){
                            f[u] = 1;
                            groups[k].pb(u);
                            q.push(u);
                        }
                    }
                }

                for(int j = 0; j < sz(groups[k]); j++){
                    //cout << groups[k][j] << ' ';
                    if(j + 1 < sz(groups[k])){
                        ans[groups[k][j]][groups[k][j + 1]] = 1;
                        ans[groups[k][j + 1]][groups[k][j]] = 1;
                    }
                    for(int x = j + 1; x < sz(groups[k]); x++){
                        if(p[groups[k][i]][groups[k][j]] != 1){
                            return 0;
                        }
                    }
                }
                //cout << '\n';
                k++;
            }

            if(k == 2){
                return -1;
            }

            for(int j = 0; j + 1 < k; j++){
                ans[groups[j][0]][groups[j + 1][0]] = 1;
                ans[groups[j + 1][0]][groups[j][0]] = 1;
            }
            ans[groups[k - 1][0]][groups[0][0]] = 1;
            ans[groups[0][0]][groups[k - 1][0]] = 1;
        }
    }


    build(ans);
    return 1;
}

/*int main(){
    cout << construct({{1, 1, 2, 2}, {1, 1, 2, 2}, {2, 2, 1, 2}, {2, 2, 2, 1}}) << '\n';
}*/

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