#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> pii;
int construct(vector<vector<int>> p) {
int N=p.size();
vector<pii> comps(N);
for(int i=0;i<N;++i) comps[i]={-1,-1};
int newcomp=0;
vector<int> newsubcomp(N,0);
for(int i=0;i<N;++i) {
if(comps[i]==pii(-1,-1)) {
comps[i]={newcomp,newsubcomp[newcomp]++};
newcomp++;
}
else if(comps[i].second<0) comps[i].second=newsubcomp[comps[i].first]++;
for(int j=i+1;j<N;++j) {
if(p[i][j]==3) return 0;
if(comps[j]==pii(-1,-1)) {
if(p[i][j]==0) continue;
if(p[i][j]==1) comps[j]=comps[i];
if(p[i][j]==2) comps[j].first=comps[i].first;
} else {
if(p[i][j]==0&&comps[i].first==comps[j].first) return 0;
if(p[i][j]==1) {
if(comps[i].first!=comps[j].first) return 0;
if(comps[i].second!=comps[j].second) {
if(comps[j].second>=0) return 0;
else comps[j].second=comps[i].second;
}
}
if(p[i][j]==2&&comps[i]==comps[j]) return 0;
}
}
}
vector<vector<vector<int>>> gr(N,vector<vector<int>>(N));
for(pii p:comps) gr[p.first][p.second].push_back(p.first);
vector<vector<int>> ans(N,vector<int>(N,0));
for(int i=0;i<N;++i) {
for(int j=0;j<N;++j) {
for(int k=1;k<gr[i][j].size();++k) ans[gr[i][j][k]][gr[i][j][0]]=ans[gr[i][j][k]][gr[i][j][0]]=1;
ans[gr[i][j][0]][gr[i][(j-1+N)%N][0]]=ans[gr[i][(j-1+N)%N][0]][gr[i][j][0]]=1;
}
}
build(ans);
return 1;
}
Compilation message
supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:42:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
42 | for(int k=1;k<gr[i][j].size();++k) ans[gr[i][j][k]][gr[i][j][0]]=ans[gr[i][j][k]][gr[i][j][0]]=1;
| ~^~~~~~~~~~~~~~~~
supertrees.cpp:46:3: error: 'build' was not declared in this scope
46 | build(ans);
| ^~~~~
