# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
397699 | priority_queue | Connecting Supertrees (IOI20_supertrees) | C++14 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
// ioi 2020, day 1, supertrees
#include <bits/stdc++.h>
using namespace std;
#define forint(i, N) for (int i = 0; i < (N); i++)
using namespace std;
void build(std::vector<std::vector<int> > b);
int construct(const vector<std::vector<int> > & p) {
int N = p.size();
vector< vector<int> > b(N, vector<int>(N, 0));
vector<int> visited(N, -1);
forint(i, N) {
if (visited[i] < 0) { // create new. All connected to i also not visited
//visited[i] = i;
vector<int> path2 = {};
//forint (j, N) {
for (int j = i+1; j < N; j++) {
/*
if (j == i) {
if (p[i][i]!=1) {
return 0;
}
continue;
}
*/
if (p[i][j] == 1) {
if (visited[j] >=0) {
return 0;
}
b[i][j] = 1;
b[j][i] = 1;
visited[j] = i;
continue;
}
if (p[i][j] == 2) {
if (visited[j] >=0) {
return 0;
}
path2.push_back(j);
//visited[j] = i;
continue;
}
if (p[i][j] == 3) {
return 0;
}
}
if (!path2.empty()) {
if (path2.size() < 2) {
return 0;
}
int last = i;
//b[i][path2[0]] = 1;
//b[path2[0]][i] = 1;
forint(j, path2.size()) {
if (visited[j] < 0) {
// make it root
b[last][path2[j]] = 1;
b[path2[j]][last] = 1;
last = path2[j];
visited[path2[j]] = i;
for (int j2 = j+1; j2 < path2.size(); j2++) {
if (visited[path2[j2]] < 0 && p[path2[j]][path2[j2]] == 1) {
b[path2[j]][path2[j2]] = 1;
b[path2[j2]][path2[j]] = 1;
visited[path2[j2]] = path2[j];
}
}
}
}
b[i][last] = 1;
b[last][i] = 1;
}
}
else { // check if it is OK
for (int j = i+1; j< N; j++) {
/*
if (p[visited[i]][i] == p[visited[i]][j]) {
if (p[i][j] != p[visited[i]][i]) {
//cout << i << " ---- " << j << " : " << p[i][j] << " ? " << p[visited[i]][i] << " -- " << visited[i] << endl;
return 0;
}
}
else {
*/
if (p[i][j] != p[visited[i]][j] * p[visited[i]][i]) {
//cout << i << " ----------------- " << j << endl;
return 0;
}
//}
//}
}
}
}
build(b);
return 1;
}