# include <iostream>
# include <fstream>
# include <list>

void read_data ( std :: istream & , int & ) ;
int ** alloc_matrix ( int ) ;
void free_matrix ( int ** , int ) ;
void print_matrix ( std :: ostream & , int ** , int ) ;
void sortare_topologica ( std :: ostream & , int ** , int ) ;
bool graph_empty ( int ** , int ) ;
void get_start ( int ** , int , std :: list <int> & ) ;

int main () {

	std :: ifstream f ("sortaret.in") ;
	std :: ofstream g ("sortaret.out") ;

	int N ;
	int M ;
	int x ;
	int y ;
	int ** matrix ;

	read_data ( f , N ) ;
	read_data ( f , M ) ;
	matrix =  alloc_matrix ( N ) ;

	for ( int i = 0 ; i < M ; i ++ ) {
	
		read_data ( f , x ) ;
		read_data ( f , y ) ;
		matrix[x][y] = 1 ;
	
	}
	
	print_matrix ( g , matrix , N ) ;
	sortare_topologica ( g , matrix , N ) ;

	free_matrix ( matrix , N ) ;
	f.close () ;
	g.close () ;
	return 0 ;

}


void sortare_topologica ( std :: ostream & g , int ** matrix , int N ) {

	std :: list <int> solutie ;
	std :: list <int> start ;
	int ok ;
	int node ;
	
	get_start ( matrix , N , start ) ;
	
	while ( ! start.empty () ) {
	
		node = start.front () ;
		start.pop_front () ;
		solutie.push_back (node) ;
		for ( int i = 0 ; i < N ; i ++ ) {
		
			if ( matrix[node][i] == 1 ) {
			
				matrix[node][i] = 0 ;
				ok = 1 ;
				for ( int j = 0 ; j < N ; j ++ ) {
				
					if ( matrix[j][i] == 1 ) {
					
						ok = 0 ;
						break ;
					
					}
				
				}
				
				if ( ok ) {
				
					start.push_back (i) ;
				
				}
			
			}
		
		}
	
	}
	
	if ( graph_empty ( matrix , N ) ) {
	
		g << " Graful are cicluri\n" ;
	
	} else {
	
		for ( std :: list <int> :: iterator it = solutie.begin () ; it != solutie.end () ; ++ it ) {
		
			g << *it << ' ' ;
		
		}
		
		g << '\n' ;
	
	}
	
	


}

void get_start ( int ** matrix , int N , std :: list <int> & start ) {

	int ok ;
	
	for ( int i = 0 ; i < N ; i ++ ) {
	
		ok = 1 ;
		for ( int j = 0 ; j < N ; j ++ ) {
		
			if ( matrix[j][i] == 1 ) {
			
				ok = 0 ;
				break ;
			
			}
		
		}
		
		if ( ok ) {
		
			start.push_back (i) ;
		
		}
	
	}

}

bool graph_empty ( int ** matrix , int N ) {

	int ok = 1 ;
	for ( int i = 0 ; i < N && ok ; i ++ ) {
	
		for ( int j = 0 ; j < N && ok ; j ++ ) {
		
			if ( matrix[i][j] == 1 ) {
			
				ok = 0 ;
			
			}
		
		}
	
	}
	
	return !ok ;

}


void print_matrix ( std :: ostream & g , int ** matrix , int N ) {

	for ( int i = 0 ; i < N ; i ++ ) {
	
		for ( int j = 0 ; j < N ; j ++ ) {
		
			g << matrix[i][j] << ' ' ;
		
		}
		
		g << '\n' ;
	
	}

}

int ** alloc_matrix ( int N ) {

	int ** matrix ;
	
	matrix = new int * [N] ;
	for ( int i = 0 ; i < N ; i ++ ) {
	
		matrix[i] = new int [N] ;
	
	}

	return matrix ;
}


void free_matrix ( int ** matrix , int N ) {

	for ( int i = 0 ; i < N ; i ++ ) {
	
		delete [] matrix[i] ;
	
	}
	
	delete [] matrix ;

}


void read_data ( std :: istream & f , int & x ) {

	f >> x ;

}