#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;
#define f first
#define s second
#define pb push_back
#define mp make_pair
#define pi pair<ll, ll>
#define sz(x) (int)((x).size())
#define all(a) (a).begin(), (a).end()

/* int f[maxn],nf[maxn],inv[maxn];
const int M=998244353;
void init(){
    inv[1]=1; for (int i=2;i<maxn;i++) inv[i]=M-1ll*(M/i)*inv[M%i]%M;
    f[0]=nf[0]=1; for (int i=1;i<maxn;i++) f[i]=1ll*f[i-1]*i%M,nf[i]=1ll*nf[i-1]*inv[i]%M;
}
int C(int x,int y){return 1ll*f[x]*nf[y]%M*nf[x-y]%M;}*/
const ll mod = 1e9+7;
ll n, k, m, mi, ma;
const ll N = 5e4 + 5;
vector<ll> a[N];
vector<ll> ans;
vector<ll> v(N, 0);

bool dfs(ll x){
	v[x] = 1;
	for(int i = 0; i<a[x].size(); i++){
		ll y = a[x][i];
		if(v[y] == 1) return 1;
		if(v[y] == 2) continue;
		bool u = dfs(y);
		if(u) return 1;
	}
	ans.pb(x + 1);
	v[x] = 2;
	return 0;
}


void solve(){
	
	ifstream cin("sortaret.in");
	ofstream cout("sortaret.out");
	
	cin >> n >> m;
	for(int i = 0; i<m; i++){
		ll x, y;
		cin >> x >> y;
		x--; y--;
		swap(x, y);
		a[x].pb(y);
	}
	
	for(int i = 0; i<n; i++){
		if(v[i] > 0) continue;
		bool u = dfs(i);
		if(u){
			cout << "-1\n";
			return;
		}
	}
	for(int i = 0; i<n; i++) cout << ans[i] << " "; cout << "\n";
}

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	
	int t=1;
	//cin >> t;
	while(t--) solve();
	
	return 0;
}