#include <bits/stdc++.h>
using namespace std;
vector< vector<int> >g;
int V,E,k,l;
bool visited[50001];
bool found[50001];
vector<int>sol;
inline void dfs(int curr)
{   printf("%d ",curr);
    visited[curr]=true;
    for(int j=0;j<g[curr].size();++j)
        if(!visited[g[curr][j]])
        dfs(g[curr][j]);
}
int main()
{
freopen("sortaret.in","r",stdin);
freopen("sortaret.out","w",stdout);
    scanf("%d%d",&V,&E);
    g.resize(V+1);
    for(int i=0;i<E;++i)
    scanf("%d%d",&k,&l),g[k].push_back(l),found[l]=1,found[k]=1;
    for(int i=1;i<=V;i++)
        if(found[i] && !visited[i])
            dfs(i);
    return 0;
}