#include <fstream>
#include <vector>
#include <bitset>
#include <queue>
using namespace std;

ifstream is("sortaret.in");
ofstream os("sortaret.out");

int n, m;
vector< vector<int> > G;
queue<int> Q;
bitset<50001> b;

void Read();
void Df(int v);
void Print();

int main()
{
    Read();
    Df(1);
    Print();
    is.close();
    os.close();
    return 0;
}
void Read()
{
    is >> n >> m;
    G.resize(n+1);
    for ( int i = 0, x, y; i < m; ++i )
    {
        is >> x >> y;
        G[x].push_back(y);
    }
}
void Df(int v)
{
    Q.push(v);
    b[v] = true;
    for ( auto it : G[v] )
        if( b[it] == false )
            Df(it);
}
void Print()
{
    while(!Q.empty())
    {
        os << Q.front() << ' ';
        Q.pop();
    }
}