#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <set>


using namespace std;

const int N=50001;
const int M=50001;

vector<int> G[N];
int quality[N];
vector<int> answer;



int main()
{
    int n,m,p,k;
    freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);

    cin>>n>>m;

    for( int i=1; i<=m; i++ )
    {
        cin>>p>>k;
        G[p].push_back(k);
        quality[k]++;
    }

    for(int i=1;i<=n;i++)
    {
        if(quality[i]==0)
        {
            for(int j=0;j<G[i].size();j++)
            {
                quality[G[i][j]]--;
            }
            answer.push_back(i);
        }
    }
    cout<<answer[0];
    for(int i=1; i<answer.size(); i++)
    {
        cout<<" "<<answer[i];
    }
    return 0;
}