#include <iostream>
#include <fstream>
#include <vector>
#include <stack>
using namespace std;
ifstream fin("ctc.in");
ofstream fout("ctc.out");
int n,m,x1,y1,viz1[100001],viz2[100001];
vector<int>graf1[100001];
vector<int>graf2[100001];
stack<int>stiva;

void dfs1(int ind)
{
    viz1[ind]=1;

    for(auto &v:graf1[ind])
    {
        if(viz1[v]==0)
        {
            dfs1(v);
        }
    }
    stiva.push(ind);
}

void dfs2(int ind)
{
    viz2[ind]=1;

    for(auto &v:graf2[ind])
    {
        if(viz2[v]==0)
        {
            dfs2(v);
        }
    }

}
void p2()
{
     while(!stiva.empty())
    {
        int nod=stiva.top();
        if(viz2[nod]==0)
            dfs2(nod);
        fout<<nod<<" ";
        stiva.pop();

    }
}
int main()
{
    fin>>n>>m;
    for(int i=1; i<=m; i++)
    {
        fin>>x1>>y1;
        graf1[x1].push_back(y1);
        graf2[y1].push_back(x1);
    }
    stiva.push(1);
    for(int i=1; i<=n; i++)
        if(viz1[i]==0)
            dfs1(1);

    return 0;
}