#include <cstdio>
#include <vector>
#include <queue>

using namespace std;
#define MAX 50005

vector<int> v[MAX], q, sol;
int n, m, pred[MAX];

bool comp(int a, int b)
{
    return pred[a] > pred[b];
}

int main()
{
    freopen("sortaret.in", "r", stdin);
    freopen("sortaret.out", "w", stdout);
    int i, a, b, tata, fiu;
    scanf("%d%d", &n, &m);
    for(i=1; i<=m; i++)
    {
        scanf("%d%d", &a, &b);
        v[a].push_back(b);
        pred[b]++;
    }
    for(i=1; i<=n; i++)
        if(!pred[i])
            q.push_back(i);

    make_heap(q.begin(), q.end(), comp);
    while(!q.empty())
    {
        tata = q.front();
        sol.push_back(tata);
        pop_heap(q.begin(), q.end());  q.pop_back();

        vector<int>::iterator it;
        for(it=v[tata].begin(); it!=v[tata].end(); ++it)
        {
            fiu = *it;
            pred[fiu]--;
            if(!pred[fiu])
            {
                q.push_back(fiu);
                push_heap(q.begin(), q.end(), comp);
            }
        }
    }
    if(sol.size() > n)
        printf("-1\n");
    else
    {
        vector<int>::iterator it;
        for(it=sol.begin(); it!=sol.end(); ++it)
            printf("%d ", *it);
    }
    return 0;
}