Submission #301304

#	Time	Username	Problem	Language	Result	Execution time	Memory
301304		Gilgamesh	Connecting Supertrees (IOI20_supertrees)	C++17	0 / 100	0 ms	256 KiB

supertrees

#include "supertrees.h"
#include <vector>

const int mxN = 1000;

using namespace std;

int parent[mxN];
int rnk[mxN];

int find(int x) 
{ 
    if(parent[x] == -1)
        parent[x] = x;
    if (parent[x] != x) { 
        parent[x] = find(parent[x]); 
    }
    return parent[x]; 
}
bool merge(int x, int y) 
{ 
    int xRoot = find(x), yRoot = find(y); 
    if (xRoot == yRoot) 
        return false; 
    if (rnk[xRoot] < rnk[yRoot]) 
        parent[xRoot] = yRoot; 
    else if (rnk[yRoot] < rnk[xRoot]) 
        parent[yRoot] = xRoot; 
    else 
    { 
        parent[yRoot] = xRoot; 
        rnk[xRoot] = rnk[xRoot] + 1; 
    } 
    return true;
} 

int construct(std::vector<std::vector<int>> p) {
    int n = p.size();
    std::vector<std::vector<int>> answer;
    for (int i = 0; i < n; i++) {
        std::vector<int> row;
        row.resize(n);
        answer.push_back(row);
    }
    bool zero = 0, one = 0, two = 0, three = 0;
    for(int i = 0; i < n; ++i){
        for(int j = 0; j < n; ++j){
            if(p[i][j] == 0) zero = true;
            else if(p[i][j] == 1) one = true;
            else if(p[i][j] == 2) two = true;
            else three = true;
        }
    }
    for(int i = 0; i < n; ++i){
        parent[i] = i;
    }
    if(zero && two && !one && !three){
        for(int i = 0; i < n; ++i){
            for(int j = i + 1; j < n; ++j){
                if(!p[i][j] && find(i) == find(j)){
                    return 0;
                }
                if(p[i][j]) merge(i, j);
            }
        }
        for(int i = 0; i < n; ++i){
            for(int j = i + 1; j < n; ++j){
                if(!p[i][j] && find(i) == find(j)) return 0;
            }
        }
        vector<int> sets[n];
        for(int i = 0; i < n; ++i){
            int rep = find(i);
            sets[rep].emplace_back(i);
        }
        for(int i = 0; i < n; ++i){
            int sz = sets[i].size();
            if(sz == 2) return 0;
            for(int j = 0; j < sz - 1; ++j){
                answer[sets[i][j]][sets[i][j + 1]] = 1;
                answer[sets[i][j + 1]][sets[i][j]] = 1;
            }
            if(sz > 1){
                answer[sets[i][0]][sets[i][sz-1]] = 1;
                answer[sets[i][sz-1]][sets[i][0]] = 1;
            }
        }
    }
    else if(zero && one && !two && !three){
        for(int i = 0; i < n; ++i){
            for(int j = i + 1; j < n; ++j){
                if(!p[i][j] && find(i) == find(j)){
                    return 0;
                }
                if(p[i][j]) merge(i, j);
            }
        }
        for(int i = 0; i < n; ++i){
            for(int j = i + 1; j < n; ++j){
                if(!p[i][j] && find(i) == find(j)) return 0;
            }
        }
        for(int i = 0; i < n; ++i){
            int rep = find(i);
            if(rep == i) continue;
            answer[rep][i] = 1;
            answer[i][rep] = 1;
        }
    }
    build(answer);
    return 1;
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 10
• Subtask 3: 0 / 19
• Subtask 4: 0 / 35
• Subtask 5: 0 / 21
• Subtask 6: 0 / 4