#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;
ifstream fin("sortaret.in");
ofstream fout("sortaret.out");

const int NMAX = 50001;

int n, m, viz[NMAX], k, f[NMAX];

vector <int> a[NMAX];

void dfs(int x)
{
    viz[x] = 1;
    for(auto it : a[x])
    {
        if(!viz[it])
        {
            viz[x] = 1;
            dfs(it);
        }
    }
    f[++k] = x;
}

void citire()
{
    int x, y;
    fin >> n >> m;
    for(int i = 1; i <= n; i++)
    {
        fin >> x >> y;
        a[x].push_back(y);
    }
}

int main()
{
    citire();
    for(int i = 1; i <= n; i++)
    {
        sort(a[i].begin(), a[i].end(), greater<int>());

    }
    for(int i = 1; i <= n; i++)
    {
        if(!viz[i])
            dfs(i);
    }

    for(int i = k; i >= 1; i--)
    {
        fout << f[i] << ' ';
    }
    return 0;
}