#include <fstream>
using namespace std;
ifstream fin("euler.in");
ofstream fout("euler.out");
int a[205][205],n,x,y,l[20000],p;


void euler(int k)
{
	for(int i = 1 ; i <= n ; i ++)
		if(a[k][i] == 1)
		{
			a[k][i] = a[i][k] = 0;
			euler(i);
		}
	l[++p] = k;
}

int main()
{int i,j;
    fin>>n;
while(fin>>i>>j)a[i][j]=a[j][i]=1;
euler(1);
//fout<<p<<endl;
for(i=1;i<=p;i++)fout<<l[i]<<" ";
    return 0;
}