#include <iostream>
using namespace std;
int main()
{
   int n, m, a[100], b[100], s[100][100], i, j;
   cin>>n>>m;
   for(i=1; i<=n; i++) cin>>a[i];
   for(j=1; j<=m; j++) cin>>b[j];
   for(i=1; i<=n; i++)
   for(j=1; j<=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;
}