#include <fstream>
#include<vector>
#include<queue>
using namespace std;
ifstream fin("sortaret.in");
ofstream fout("sortaret.out");
vector<int>a[50001];
queue<int>q;
int n,m,x,y,gr[50001],k;
int main()
{
    fin>>n>>m;
    for(int i=1;i<=n;i++)
    {
        fin>>x>>y;
        a[x].push_back(y);
        gr[y]++;
    }
    for(int i=1;i<=n;i++)
        if(!gr[i])
          q.push(i);
    while(!q.empty())
    {
        k=q.front();
        fout<<k<<" ";
        q.pop();
        for(int i=0;i<a[k].size();i++)
        {
            gr[a[k][i]]--;
            if(gr[a[k][i]]==0)
                q.push(a[k][i]);
        }
    }
    return 0;
}