#include <iostream>
#include <vector>
#include <queue>
#include <fstream>
#include <stack>
#include <algorithm>
using namespace std;
#define Nmax 100007
#define Rezolvare 1
const char iname[] = "bfs.in";
const char oname[] = "bfs.out";
vector<int> rev[Nmax];
vector<int> aux;
ifstream f(iname);
ofstream g(oname);
class Graph{
public:
Graph(int n, int m);
~Graph();
virtual void add_muchie(int x, int y){}
bool is_correct_graph(vector<int> grade);
private:
protected:
vector<int> la[Nmax]; //lista de adiacenta;
int n,m; //numarul de noduri si numarul de muchii
};
bool Graph::is_correct_graph(vector<int> grade)
{
sort(grade.begin(),grade.end(),greater <int>());
while(grade[0]!=0)
{
int v=grade[0];
grade.erase(grade.begin()+0);
if(v>grade.size())
return false;
for(int i=0;i<v;i++)
{
grade[i]--;
if(grade[i]<0)
return false;
}
sort(grade.begin(),grade.end(),greater <int>());
}
return true;
}
class Undirected: public Graph{
public:
Undirected(int n, int m);
~Undirected();
void add_muchie(int x,int y)
{
la[x].push_back(y);
la[y].push_back(x);
}
void dfs(int start,int visited[]);
private:
};
int nr_conex=0;
void Undirected::dfs(int start,int visited[])
{
visited[start] = nr_conex;
for(auto i:la[start])
{
if(!visited[i])
dfs(i,visited);
}
}
Undirected::Undirected(int n, int m): Graph(n,m)
{
}
Undirected::~Undirected()
{
}
class Directed: public Graph{
public:
Directed(int n,int m);
~Directed();
void add_muchie(int x,int y);
void bfs(int start, int visited[],int dist[]);
void findCTC();
void reverse();
void topologic();
private:
void dfs_plus(int i,stack<int> &my_stack,int visited[]);
void dfs_reverse(int i,vector <int>& aux,int visited[]);
//void dfs_topologic(int i,stack <int>&Stack,int visited[]);
};
void Directed::topologic()
{
stack <int> Stack;
int visited[n];
for(int i=1; i<=n;i++)
visited[i]=0;
for(int i=1;i<=n;i++)
if(visited[i]==0)
dfs_plus(i,Stack,visited);
while(!Stack.empty())
{
g<<Stack.top()<<" ";
Stack.pop();
}
}
void Directed::dfs_reverse(int i,vector <int>& aux,int visited[])
{
visited[i]=1;
for(auto j:rev[i])
{
if(!visited[j])
dfs_reverse(j,aux,visited);
}
aux.push_back(i);
}
void Directed::findCTC()
{
int visited[n];
vector< vector<int> > sol;
for(int i=1;i<=n;i++)
visited[i]=0;
stack<int> my_stack;
for(int i=1;i<=n;i++)
if(!visited[i])
dfs_plus(i,my_stack,visited);
for(int i=1;i<=n;i++)
visited[i]=0;
int scc = 0;
while(!my_stack.empty())
{
int cur = my_stack.top();
my_stack.pop();
if(!visited[cur])
{
aux = vector<int>();
dfs_reverse(cur,aux,visited);
sol.push_back(aux);
scc++;
}
}
g<<scc<<"\n";
cout<<sol[1].size();
for(int i=0;i<sol.size();i++)
{
for(int j=0;j<sol[i].size();j++)
g<<sol[i][j]<<" ";
g<<"\n";
}
}
void Directed::reverse()
{
for(int i=1;i<=n;i++)
{
for(int j:la[i])
rev[j].push_back(i);
}
}
void Directed::dfs_plus(int i,stack<int> &my_stack,int visited[])
{
visited[i]=1;
for(int j:la[i])
{
if(!visited[j])
dfs_plus(j,my_stack,visited);
}
my_stack.push(i);
}
Directed::Directed(int n, int m): Graph(n,m)
{
}
Directed::~Directed()
{
}
void Directed::add_muchie(int x,int y)
{
la[x].push_back(y);
}
void Directed::bfs(int start, int visited[],int dist[]){
queue <int> coada;
visited[start]=true;
coada.push(start);
dist[start] = 0;
while(!coada.empty())
{ start = coada.front();
coada.pop();
for(auto i:la[start])
{
if(!visited[i])
{
visited[i] = true;
coada.push(i);
dist[i]=dist[start]+1;
}
}
}
}
Graph::Graph(int n=0, int m=0):n(n),m(m)
{
}
Graph::~Graph()
{
}
int main()
{
int n,m,s;
int x,y;
switch(Rezolvare)
{
case 1:
{
f>>n>>m>>s;
Directed grf(n,m);
for(int i=0;i<m;i++)
{
f>>x>>y;
grf.add_muchie(x,y);
}
f.close();
int visited[n],dist[n];
for(int i=0;i<=n;i++)
visited[i]=dist[i]=0;
grf.bfs(s,visited,dist);
for(int i=1;i<=n;i++)
{
if(visited[i])
g<<dist[i]<<" ";
else g<<-1<<" ";
}
break;
}
case 2:
{
f>>n>>m;
Undirected grf(n,m);
int visited[n];
for(int i=0;i<m;i++)
{
f>>x>>y;
grf.add_muchie(x,y);
}
for(int i=0;i<=n;i++)
visited[i]=0;
for(int i=1;i<=n;i++)
if(!visited[i])
{
nr_conex++;
grf.dfs(i,visited);
}
g<<nr_conex;
break;
}
case 3:
{
f>>n>>m;
Directed grf(n,m);
for(int i=0;i<m;i++)
{
f>>x>>y;
grf.add_muchie(x,y);
}
grf.reverse();
grf.findCTC();
break;
}
case 4:
{vector<int> check;
int number;
cin>>number;
for(int i=0;i<number;i++)
{
int c;
cin>>c;
check.push_back(c);
}
Graph grf(n);
if(grf.is_correct_graph(check))
cout<<"DA";
else cout<<"NU";
}
case 5:
{
f>>n>>m;
Directed grf(n,m);
for(int i=0;i<m;i++)
{
f>>x>>y;
grf.add_muchie(x,y);
}
f.close();
grf.topologic();
}
}
g.close();
return 0;
}