#include "supertrees.h"
#include <bits/stdc++.h>
//#include "grader.cpp"
using namespace std;
#define pb push_back
#define mp make_pair
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
struct DSU{
vi parent, size;
void init(int n){
for(int i = 0; i < n; i++){
parent.pb(i);
size.pb(1);
}
}
int find_parent(int v){
if(parent[v] == v) return v;
return parent[v] = find_parent(parent[v]);
}
void merge(int a, int b){
a = find_parent(a);
b = find_parent(b);
if(a != b){
if(size[b] > size[a])
swap(a, b);
parent[b] = a;
size[a] += size[b];
}
}
};
int construct(vector<vi> p) {
int n = p.size();
vector<vi> answer;
bool possible = true;
for(int i = 0; i < n; i++){
for(auto t : p[i]){
if(t == 3) possible = false;
}
}
for(int i = 0; i < n; i++){
vi pom(n,0);
answer.pb(pom);
}
DSU dsu;
dsu.init(n);
for(int i = 0; i < n; i++){
for(int j = i+1; j < n; j++){
if(p[i][j] == 1){
dsu.merge(i, j);
dsu.merge(j, i);
}
else
continue;
}
}
for(int i = 0; i < n; i++){
for(int j = i + 1; j < n; j++){
if(p[i][j] == 0 && find_parent(i) == find_parent(j)){
possible = false;
}
}
}
int last[n];
memset(last, -1, sizeof last);
for(int i = 0; i < n; i++){
int a = dsu.find_parent(i);
if(last[a] == -1) last[a] = i;
else{
answer[i][last[a]] = 1;
answer[last[a]][i] = 1;
last[a] = i;
}
}
if(!possible) return 0;
build(answer);
return 1;
}
Compilation message
supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:63:23: error: 'find_parent' was not declared in this scope
63 | if(p[i][j] == 0 && find_parent(i) == find_parent(j)){
| ^~~~~~~~~~~
