#include <bits/stdc++.h>

using namespace std;
int x,y,n,m,prd[50001],viz[50001],i,nd;
vector <int> srtp,mc[50001];
queue <int> q;
int main()
{
    freopen("sortaret.in","r",stdin);
    freopen("sortaret.out","w",stdout);
    scanf("%d%d",&n,&m);
    for(i=1;i<=n;i++)
    {
        scanf("%d%d",&x,&y);
        mc[x].push_back(y);
        prd[y]=1;
    }
    for(i=1;i<=n;i++)
        if(!prd[i]) q.push(i),viz[i]=1;
    while(!q.empty())
    {
        nd=q.front();
        srtp.push_back(nd);
        q.pop();
        for(i=0;i<mc[nd].size();i++)
            if(!viz[mc[nd][i]])
            {
                viz[mc[nd][i]]=1;
                q.push(mc[nd][i]);
            }
    }
    for(i=0;i<srtp.size();i++)
        printf("%d ",srtp[i]);
    return 0;
}