#include <iostream>

using namespace std;

int main()
{
   int n, m, a[100], s[100][100];
cin>>n>>m;
    for (int i=1; i<=n; i++) cin>>a[j];
    for (int j=1; j<=m; j++) cin>>b[j];
    for (int i=1; i<=n; i++)
    for (int j=1; i<=m; j++)
if (a[i]==b[j]) { s[i][j]=s[i-1][j-1]+1; cout<<a[i]<<" "; }
                    else
  s[i][j]=max(s[i-1][j], s[i][j-1]);
  cout<<"\n"<<s[n][m]
     return 0;

}