#include<iostream>
#include<vector>
using namespace std;

#define NMAX 50005

int n,m,inc[NMAX];
vector<int>g[NMAX];
void topsort(int i){
    cout<<i<<" ";
    for(auto it:g[i]){
        --inc[it];
        if(!inc[it]){
            --inc[it];
            topsort(it);
        }
    }
}
signed main(){
#ifndef LOCAL
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
#endif // LOCAL
    freopen("sortaret.in","r",stdin);
    freopen("sortaret.out","w",stdout);
    cin>>n>>m;
    for(int i=1;i<=n;++i){
        int x,y;
        cin>>x>>y;
        g[x].push_back(y);
        ++inc[y];
    }
    for(int i=1;i<=n;++i){
        if(!inc[i])topsort(i);
    }
    return 0;
}