/*
ID: Yoana Zelova zelova1
PROG:
LANG: C++
*/
#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cmath>
#include<string>
#include<stack>
#include<queue>
#include<vector>
#include<fstream>
using namespace std;
long long n,i,a[2048],b[2048],l,r,c[512],m,used[512],li,ri;
int main()
{
    freopen ("lottery.in","r",stdin);
    freopen ("lottery.out","w",stdout);
    cin>>n;
    for(i=1;i<=n;i++)
    {
       scanf("%lld%lld",&a[i],&b[i]);
       m=max(m,a[i]);
       m=max(m,b[i]);
    }
    for(i=1;i<=m;i++)
        c[i]=i;
    for(i=1;i<=n;i++)
    {

        l=lower_bound(c+1,c+m,a[i])-c;
        r=lower_bound(c+1,c+m,b[i])-c;
        //cout<<l<<" "<<r<<endl;
        if(l>r)
        {
            if(used[a[i]]==1&&used[b[i]]==1)
            {
                li=lower_bound(used+l,used+m,0)-used;
                ri=lower_bound(used+r,used+m,0)-used;
                swap(c[li],c[r]);
                swap(c[ri],c[l]);
            }
            else if(used[a[i]]==1)
            {
                li=lower_bound(used+l,used+m,0)-used;
                swap(c[li],c[r]);
            }
            else if(used[b[i]]==1)
            {
                ri=lower_bound(used+r,used+m,0)-used;
                swap(c[l],c[ri]);
            }
            else swap(c[l],c[r]);
        }
        used[a[i]]=1;
        used[b[i]]=1;
    }
    for(i=1;i<m;i++)
       cout<<c[i]<<" ";
    cout<<c[m]<<endl;
    return 0;
}