Submission #823019

#TimeUsernameProblemLanguageResultExecution timeMemory
823019vjudge1Split the Attractions (IOI19_split)C++17
40 / 100
53 ms12920 KiB
#include "split.h"
#include <bits/stdc++.h>

using namespace std;

const int N = 100100;

vector < int > adj[N], ans, sz(N);
vector < pair < int, int > > cls;
int lst, flag = 1;

void dfs1(int i, int &c, int cc) {
    -- c;
    ans[i] = cc;
    for(auto &j : adj[i]) {
        if(!ans[j] && c) {
            dfs1(j, c, cc);
        } else if(!c && !ans[j]) {
            lst = j;
        }
    }
}

void solve1() {
    int cr = 0, n = ans.size();
    for(int i = 0; i < n; ++ i) {
        if(adj[i].size() == 1) {
            cr = i;
            break;
        }
    }
    dfs1(cr, cls[0].first, cls[0].second);
    dfs1(lst, cls[1].first, cls[1].second);
    dfs1(lst, cls[2].first, cls[2].second);
}

void solve2() {
    dfs1(0, cls[1].first, cls[1].second);
    ans[lst] = cls[0].second;
    for(auto &i : ans) {
        if(!i) {
            i = cls[2].second;
        }
    }
}

void dfs(int i, int k) {
    sz[i] = 1;
    for(auto &j : adj[i]) {
        if(j != k) {
            dfs(j, i);
            if(flag && sz[j] >= cls[0].first && (int)ans.size() - sz[j] >= cls[1].first) {
                ans[i] = cls[1].second;
                dfs1(j, cls[0].first, cls[0].second);
                dfs1(i, cls[1].first, cls[1].second);
                flag = 0;
            } else if(flag && sz[j] >= cls[1].first && (int)ans.size() - sz[j] >= cls[0].first) {
                ans[j] = cls[1].second;
                dfs1(i, cls[0].first, cls[0].second);
                dfs1(j, cls[1].first, cls[1].second);
                flag = 0;
            }
            sz[i] += sz[j];
        }
    }
}

void solve3() {
    dfs(0, 0);
    for(auto &i : ans) {
        if(!i && !flag) {
            i = cls[2].second;
        }
    }
}

vector<int> find_split(int n, int a, int b, int c, vector<int> p, vector<int> q) {
    for(int i = 0; i < (int)p.size(); ++ i) {
        adj[p[i]].push_back(q[i]);
        adj[q[i]].push_back(p[i]);
    }
    ans.resize(n);
    cls = {{a, 1}, {b, 2}, {c, 3}};
    sort(cls.begin(), cls.end());
    if(cls[0].first == 1) {
        solve2();
    } else if((int)p.size() == n - 1) {
        solve3();
    } else {
         solve1();
    }
    return ans;
}
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...