| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 788274 | mannshah1211 | 슈퍼트리 잇기 (IOI20_supertrees) | C++17 | 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.
#include <bits/stdc++.h>
#include "supertrees.h"
using namespace std;
void build(vector<vector<int>> b);
struct DSU {
vector<int> link, siz;
DSU (int n) : link(n), siz(n, 1) {
iota(link.begin(), link.end(), 0ll);
}
int get(int x) {
if (link[x] == x) {
return x;
}
return link[x] = get(link[x]);
}
bool unite(int a, int b) {
a = get(a), b = get(b);
if (a == b) {
return false;
}
if (siz[a] < siz[b]) {
swap(a, b);
}
link[b] = a;
siz[a] += siz[b];
return true;
}
bool same(int a, int b) {
return (get(a) == get(b));
}
};
int construct(vector<vector<int>> p) {
vector<vector<int>> b(p.size(), vector<int>(p.size()));
DSU ds(n);
for (int i = 0; i < p.size(); i++) {
for (int j = i + 1; j < p.size(); j++) {
if (p[i][j] != 0) {
ds.unite(i, j);
}
}
}
for (int i = 0; i < p.size(); i++) {
for (int j = i + 1; j < p.size(); j++) {
if (p[i][j] == 0 && ds.same(i, j)) {
return 0;
} else if (p[i][j] == 1 && !ds.same(i, j)) {
return 0;
}
}
}
vector<vector<int>> conncomps;
for (int i = 0; i < p.size(); i++) {
conncomps[ds.get(i)].push_back(i);
}
for (int i = 0; i < conncomps.size(); i++) {
for (int j = 0; j < (int) conncomps[i].size() - 1; j++) {
b[conncomps[i][j]][conncomps[i][j + 1]] = 1;
b[conncomps[i][j + 1]][conncomps[i][j]] = 1;
}
}
build(b);
return 1;
}