#include<fstream>
#include<iostream>
using namespace std;
int a[1000],b[1000],c[1000][1000], sol[1000],n,m;

int main()
{
    int i,j;
    ifstream in("cmlsc.in");
    ofstream out("cmlsc.out");
    in>>n>>m;
    for( i=1;i<=n;i++)
        in>>a[i];
    for( i=1;i<=m;i++)
        in>>b[i];

    for( i=1;i<=n;i++)
        for( j=1;j<=m;j++)
        {
            if(a[i]==b[j])
                c[i][j]=1+c[i-1][j-1];
            else
                c[i][j]=max(c[i-1][j],c[i][j-1]);
        }

    for( i=1;i<=n;i++)
    {
        for( j=1;j<=m;j++)
            cout<<c[i][j]<<" ";
        cout<<"\n";
    }

    i=n;j=m;
    int s=1;
    while(i)
    {
        if(a[i]==b[j])
        {
            sol[s]=a[i];
            i--; j--;
            s++;
        }
        else
        {
            if(c[i][j-1]>c[i-1][j])
                j--;
            else
                i--;
        }
    }
    out<<s-1<<"\n";
    for(i=s-1;i>=1;i--)
        out<<sol[i]<<" ";
    in.close();
    out.close();
    return 0;
}