/*
TASK:platka
LANG:C++
*/
#include<iostream>
using namespace std;
int n,m;
int ming=2000;
int q[22000],brq=0;
int a[2000][2000];
void pechat()
{
     int i;
     for (i=0;i<brq-2;i++)
         cout<<q[i]<<" ";
     cout<<q[i+1];
//       cout<<endl<<"  "<<a[5][2]<<" ";
     cout<<"\n";
     exit(0);
}
     
void dfs(int v)
{

     //cout<<v<<endl;
     int i,j,e=0,brg=0;
//     for(i=0;i<brq;i++)
//                       cout<<q[i]<<" ";
     
     for (i=0;i<=n;i++)
         {
         for (j=0;j<=n;j++)
             if(a[i][j]==1){e=1;brg++;}
         }
     if(brg<ming)ming=brg;
     if(e!=1){q[brq]=v;brq++;pechat();}
//     cout<<"  "<<i<<" "<<j;
//       cout<<"  "<<a[0][7]<<" ";
//     cout<<endl;
     for (j=0;j<=n;j++)
         if(a[v][j]==1){a[v][j]=0;a[j][v]=0;q[brq]=j;brq++; dfs(j);a[v][j]=1;a[j][v]=1;brq--;}
}
     
int main()
{
    int i,j,x,y,min=2000;
    cin>>n>>m;
    for (i=0;i<m;i++)
        {cin>>x>>y;
        if(x<min)min=x;
        if(y<min)min=y;
        a[x][y]=1;a[y][x]=1;
        }
    q[brq]=min;
    brq++;
    dfs(min);
//    system("pause");
      printf("Sorry, Pesho %d\n",ming);
    return 0;
}
