Submission #1212628

#	Time	Username	Problem	Language	Result	Execution time	Memory
1212628		guagua0407	Split the Attractions (IOI19_split)	C++20	40 / 100	1924 ms	14288 KiB

split

#include "split.h"
//#include "grader.cpp"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define f first
#define s second
#define all(x) x.begin(),x.end()
#define _ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

vector<int> find_split(int n, int a, int b, int c, vector<int> p, vector<int> q) {
    auto stt=clock();
    vector<pair<int,int>> vec={{a,1},{b,2},{c,3}};
    sort(all(vec));
    vector<vector<int>> adj(n);
    int m=(int)p.size();
    for(int i=0;i<m;i++){
        adj[p[i]].push_back(q[i]);
        adj[q[i]].push_back(p[i]);
    }
    vector<int> C(n,vec[2].s);
    vector<bool> used(n,false);
    mt19937 rng(time(NULL));
    vector<int> st;
    vector<int> st2;
    while(clock()-stt<1.9*CLOCKS_PER_SEC){
        int t;
        function<void(int,int)> dfs2=[&](int v,int p){
            //cout<<v<<' '<<p<<'\n';
            st.push_back(v);
            used[v]=true;
            if((int)st.size()==t) return;
            shuffle(all(adj[v]),rng);
            for(auto u:adj[v]){
                if(u==p or used[u]) continue;
                dfs2(u,v);
                if((int)st.size()==t) return;
            }
        };
        used=vector<bool>(n,false);
        t=vec[0].f;
        int x=abs((int)rng())%n;
        dfs2(x,-1);
        st2=st;
        st.clear();
        t=n;
        for(int x=0;x<n;x++){
            if(used[x]) continue;
            dfs2(x,-1);
            if((int)st.size()<vec[1].f){
                st.clear();
            }
            else{
                break;
            }
        }
        if(st.empty()) continue;
        for(auto v:st2){
            C[v]=vec[0].s;
        }
        for(int i=0;i<vec[1].f;i++){
            C[st[i]]=vec[1].s;
        }
        return C;
    }
    return vector<int>(n,0);
}
/*
6 5
2 2 2
0 1
1 2
2 3
3 4
4 5
*/

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