Submission #300597

#	Time	Username	Problem	Language	Result	Execution time	Memory
300597		lohacho	Connecting Supertrees (IOI20_supertrees)	C++14	100 / 100	286 ms	22408 KiB

supertrees

#include "supertrees.h"
#include <bits/stdc++.h>
using namespace std;

struct dsu{
    vector < int > pr, rk;
    int N;
    dsu(){}
    dsu(int n):N(n){
        pr.resize(N), rk.resize(N);
        for(int i = 0; i < N; ++i) pr[i] = i, rk[i] = 1;
    }
    inline int get(int x){
        return x == pr[x] ? x : pr[x] = get(pr[x]);
    }
    inline bool unite(int x, int y){
        x = get(x), y = get(y);
        if(x != y){
            if(rk[x] < rk[y]) swap(x, y);
            pr[y] = x, rk[x] += rk[y];
            return true;
        }
        return false;
    }
}all(1004), one(1004);
vector < int > circle[1004], line[1004];

int construct(std::vector<std::vector<int>> p) {
	int N = p.size();
	std::vector<std::vector<int>> answer;
	answer.resize(N);
    for(int i = 0; i < N; ++i){
        answer[i].resize(N);
        for(int j = 0; j < N; ++j){
            if(p[i][j] == 3){
                return 0;
            }
            if(p[i][j]){
                all.unite(i, j);
            }
            if(p[i][j] == 1){
                one.unite(i, j);
            }
        }
    }
    for(int i = 0; i < N; ++i){
        for(int j = 0; j < N; ++j){
            if(!p[i][j] && all.get(i) == all.get(j)) return 0;
            if(p[i][j] == 2 && one.get(i) == one.get(j)) return 0;
        }
    }
    for(int i = 0; i < N; ++i){
        if(one.get(i) == i){
            circle[all.get(i)].push_back(i);
        }
        line[one.get(i)].push_back(i);
    }
    for(int i = 0; i < N; ++i){
        if((int)circle[i].size() == 2){
            return 0;
        }
        for(int j = 0; j < (int)circle[i].size() - 1; ++j){
            answer[circle[i][j]][circle[i][j + 1]] = answer[circle[i][j + 1]][circle[i][j]] = 1;
        }
        if((int)circle[i].size() >= 3){
            answer[circle[i][0]][circle[i].back()] = answer[circle[i].back()][circle[i][0]] = 1;
        }
        for(int j = 0; j < (int)line[i].size() - 1; ++j){
            answer[line[i][j]][line[i][j + 1]] = answer[line[i][j + 1]][line[i][j]] = 1;
        }
    }
    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