#include<iostream>
#include<cstring>
using namespace std;
const int N = 1e5 + 5;
int e[N], ne[N], d[N], h[N], q[N], id;
bool st[N];
 int n, m;
void add(int a, int b){
    e[id] = b;
    ne[id] = h[a];
    h[a] = id++;
    d[b]++;
}

int ans[N];
int  cnt = 0; 

void bfs(){
    int hh = 1 , tt =  1;
    bool found = false;
    for(int i = 1; i <= n; i++)
        if(d[i] == 0) {q[++tt] = i; found = true;}

    if(!found) cout << -1;
    else
    while(hh <= tt){
        int k = q[hh++];
        if(!st[k])
        {
            if(k) ans[cnt++] = k;

            st[k] = true;

        }
        for(int i = h[k]; i != -1; i = ne[i]){
            int r = e[i];
            d[r] --;
            if(d[r] == 0) q[++tt] = r;
        }
    }

}

int main(){
    memset(h, -1, sizeof h);
    cin>>n>>m;
    for(int i = 0; i < m; i++){
        int a, b;
        cin>>a>>b;
        add(a, b);
    }
    bfs();
    if(cnt == n) 
        for(int i = 0 ; i < n; i++) cout << ans[i] << " ";
    else cout << -1 ;
    return 0;
}