Submission #335956

#	Time	Username	Problem	Language	Result	Execution time	Memory
335956		richyrich	Connecting Supertrees (IOI20_supertrees)	C++17	100 / 100	405 ms	24300 KiB

supertrees

#include "supertrees.h"
#include <vector>
#include <bits/stdc++.h>
using namespace std;
const int N = 1e3+3;
const int inf = 1e9;
std::vector<std::vector<int>> answer;
int par1[N], ran1[N], par2[N], ran2[N];
int find_p1(int a) {
    return (a == par1[a]) ? a : find_p1(par1[a]);
}
int find_p2(int a) {
    return (a == par2[a]) ? a : find_p2(par2[a]);
}
void unitee1(int a, int b) {
    a = find_p1(a), b = find_p1(b);
    if(a == b) return;
    if(ran1[a] < ran1[b]) swap(a, b);
    par1[b] = par1[a];
    if(ran1[a]==ran1[b]) ran1[a]++;
}
void unitee2(int a, int b) {
    a = find_p2(a), b = find_p2(b);
    if(a == b) return;
    if(ran2[a] < ran2[b]) swap(a, b);
    par2[b] = par2[a];
    if(ran2[a]==ran2[b]) ran2[a]++;
}
int construct(std::vector<std::vector<int>> p) {
    int n = p.size();
    for (int i = 0; i < n; i++) {
        std::vector<int> row;
        row.resize(n);
        answer.push_back(row);
    }
    for(int i = 0; i < n; i++) par2[i] = par1[i] = i, ran2[i] = ran1[i] = 1;
    

    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            if(p[i][j]==3) return 0;
            if(p[i][j] == 1) {
                unitee1(i, j);
            }
        }
    }
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            answer[i][j] = 0;
            if(i==j) continue;
            if(p[i][j] == 0 && find_p1(i)==find_p1(j)) return 0;
            if(p[i][j]==1) {
                int pp = find_p1(i);
                if(pp != i)answer[pp][i] = 1, answer[i][pp] = 1;
                if(pp != j)answer[pp][j] = 1, answer[j][pp] = 1;
            }
        }
    }
    

    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            if(p[i][j] == 2) {
                unitee2(find_p1(i), find_p1(j));
            }
        }
    }
    map<int, set<int>> M;
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            if(i==j) {
                answer[i][j] = 0;
                continue;
            }
            int a = find_p1(i), b = find_p1(j);
            if(p[i][j] == 0 && find_p2(a)==find_p2(b)) return 0;
            if(p[i][j]== 2 && find_p2(a)==find_p2(b)) {
                int pp = find_p2(a);
                if(pp != a)M[pp].insert(a);
                if(pp != b)M[pp].insert(b);
            }
        }
    }
    for(auto c : M) {
        int f = c.first, prev = c.first;
        for(auto x : c.second) {
            answer[prev][x] = 1, answer[x][prev] = 1;
            prev = x;
        }
        if(c.second.size() > 1){
            answer[f][prev] = answer[prev][f] = 1;
        }
        else {
            return 0;
        }
    }
    build(answer);
    return 1;
}

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