Submission #161772

#	Time	Username	Problem	Language	Result	Execution time	Memory
161772		andrew	Split the Attractions (IOI19_split)	C++17	11 / 100	990 ms	1048576 KiB

split

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

#define fi first
#define se second
#define pll pair<ll, ll>
#define pii pair<int, int>


using namespace std;
typedef long long ll;
typedef long double ld;
const ll MAXN = 1123456;
const ll N = 2e5;

vector <int> v[MAXN];

ll t[MAXN], P[MAXN];

void dfs(ll x, ll pr){
    P[x] = pr;
    t[x] = 1;
    for(auto to : v[x])if(to != pr){
        t[x] += t[to];
        dfs(to, x);
    }
}

vector<int> find_split(int n, int a, int b, int c, vector<int> p, vector<int> q) {
    int m = p.size(), mx = 0;

    for(int i = 0; i < m; i++){
        v[p[i]].push_back(q[i]);
        v[q[i]].push_back(p[i]);
        mx = max(mx, (int)v[p[i]].size());
        mx = max(mx, (int)v[q[i]].size());
    }

    vector <int> res(n);
    if(a == 1){
        queue <int> q;
        int start = 0;
        q.push(start);
        vector <bool> f(n);
        f[start] = 1;

        while(!q.empty()){
            int x = q.front();
            q.pop();
            if(!b)break;
            b--;
            res[x] = 2;
            for(auto to : v[x])if(!f[to]){
                f[to] = 1;
                q.push(to);
            }
        }

        for(int i = 0; i < n; i++)if(res[i] == 0){res[i] = 1; break;}
        for(int i = 0; i < n; i++)if(res[i] == 0)res[i] = 3;
        return res;
    }else{
        int start = 0;
        for(int i = 0; i < n; i++)if(v[i].size() == 1)start = i;
        vector <ll> cnt(3);
        vector <bool> f(n);
        cnt[0] = a;
        cnt[1] = b;
        cnt[2] = c;
        vector <ll> p(3);
        p[0] = 1;
        p[1] = 2;
        p[2] = 3;
        for(int i = 0; i < 3; i++)
            for(int j = i + 1; j < 3; j++)if(cnt[p[i] - 1] > cnt[p[j] - 1])swap(p[i], p[j]);
        dfs(start, 0ll);

        for(int i = 0; i < n; i++)if(t[i] >= cnt[p[0] - 1] && n - t[i] >= cnt[p[1] - 1]){
            queue <int> q;
            f[i] = 1;
            f[P[i]] = 1;
            res[P[i]] = p[0];
            cnt[p[0] - 1]--;
            q.push(P[i]);
            while(!q.empty()){
                int x = q.front();
                q.pop();
                res[x] = p[0];
                for(auto to : v[x])if(!f[to] && cnt[p[0] - 1]){
                    cnt[p[0] - 1]--;
                    q.push(to);
                }
            }
            res[i] = p[1];
            cnt[p[0] - 1]--;
            q.push(i);
            while(!q.empty()){
                int x = q.front();
                q.pop();
                res[x] = p[1];
                for(auto to : v[x])if(!f[to] && cnt[p[1] - 1]){
                    cnt[p[1] - 1]--;
                    q.push(to);
                }
            }
            for(auto &j : res)if(j == 0)j = p[2];
            return res;
        }
        return res;
    }
	return res;
}

• Subtask 1: 0 / 7
• Subtask 2: 11 / 11
• Subtask 3: 0 / 22
• Subtask 4: 0 / 24
• Subtask 5: 0 / 36