#include <bits/stdc++.h>
#include "supertrees.h"
#define inf 1000000007
#define mod 1000000007
#define rnd() rand_num()
#define bigrnd() dis(rand_num)
//#pragma GCC optimize("Ofast","inline","-ffast-math")
//#pragma GCC target("avx,sse2,sse3,sse4,mmx")
//#define int long long
using namespace std;
unsigned sed=std::chrono::system_clock::now().time_since_epoch().count();
mt19937 rand_num(sed);
uniform_int_distribution<long long> dis(0,inf);
template <typename T> void read(T &x){
x=0;char ch=getchar();int fh=1;
while (ch<'0'||ch>'9'){if (ch=='-')fh=-1;ch=getchar();}
while (ch>='0'&&ch<='9')x=x*10+ch-'0',ch=getchar();
x*=fh;
}
template <typename T> void write(T x) {
if (x<0) x=-x,putchar('-');
if (x>9) write(x/10);
putchar(x%10+'0');
}
template <typename T> void writeln(T x) {
write(x);
puts("");
}
int n;
int fa[1005];
int g[1005][1005];
int fnd(int x)
{
if(fa[x]!=x) fa[x]=fnd(fa[x]);
return fa[x];
}
int construct(vector<vector<int>> p)
{
n=p.size();
for(int i=0;i<n;++i)
fa[i]=i;
for(int i=0;i<n;++i)
for(int j=0;j<n;++j)
if(p[i][j]==3)
return 0;
else if(p[i][j]!=0)
fa[fnd(i)]=fnd(j);
for(int i=0;i<n;++i)
for(int j=0;j<n;++j)
if(p[i][j]==0&&fnd(i)==fnd(j))
return 0;
for(int i=0;i<n;++i)
fa[i]=i;
for(int i=0;i<n;++i)
for(int j=0;j<n;++j)
if(p[i][j]==1)
fa[fnd(i)]=fnd(j);
for(int i=0;i<n;++i)
for(int j=0;j<n;++j)
if(p[i][j]==2&&fnd(i)==fnd(j))
return 0;
vector<int> vec;
bool flag=false;
for(int i=0;i<n;++i)
if(fnd(i)==i)
vec.push_back(i);
for(int i=0;i<n;++i)
for(int j=0;j<n;++j)
if(p[i][j]==2)
flag=true;
if(flag&&vec.size()<3) return 0;
if(flag)
{
for(int i=0;i+1<vec.size();++i)
g[vec[i]][vec[i+1]]=g[vec[i+1]][vec[i]]=1;
if(vec.size()>1) g[vec[0]][vec[vec.size()-1]]=g[vec[vec.size()-1]][vec[0]]=1;
}
for(int i=0;i<n;++i)
if(fnd(i)!=i)
g[fnd(i)][i]=g[i][fnd(i)]=1;
vector<vector<int>> ans;
for(int i=0;i<n;++i)
{
vector<int> tmp;
for(int j=0;j<n;++j)
tmp.push_back(g[i][j]);
ans.push_back(tmp);
}
return ans;
}
Compilation message
supertrees.cpp: In function 'int construct(std::vector<std::vector<int> >)':
supertrees.cpp:74:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
74 | for(int i=0;i+1<vec.size();++i)
| ~~~^~~~~~~~~~~
supertrees.cpp:89:9: error: cannot convert 'std::vector<std::vector<int> >' to 'int' in return
89 | return ans;
| ^~~
