C++ :

#include <cstdio>
#include <cstring>
#include <queue>

using namespace std;
/*
struct queue{
    int head,tail,data[300000];
    void pop(){head++;return;}
    void push(int t){data[++tail]=t;return;}
    int front(){return data[head];}
};*/

int n,m,ac;
bool map[2001][2001],check[2001];int indgr[2001],p,path[2001],px[2001][2001];

int main()
{
	while(scanf("%d%d",&n,&m)==2)
	{
		memset(map,0,sizeof(map));
		memset(px,0,sizeof(px));
	    for(int i=1;i<=m;i++)
	    {
	        memset(check,0,sizeof(check));
	        scanf("%d",&p);
	        for(int j=1;j<=p;j++)
	        {
	            scanf("%d",&ac);
	            path[j]=ac;
	            check[ac]=1;
	        }
	        for(int k=path[1]+1;k<path[p];k++)
	        {
	            if(check[k]) continue;
	            for(int j=1;j<=p;j++)
	            {
	                if(!map[k][path[j]])
	                {
	                    px[k][++px[k][0]]=path[j];
	                    map[k][path[j]]=1;
	                    indgr[path[j]]++;
	                }
	            }
	        }
	    }
	    int s=0,sz=0;
	    queue<int> que;
	    for(int i=1;i<=n;i++)
	    {
	        if(indgr[i]==0)
	        {
	            sz++;
	            que.push(i);
	        }
	    }
	    while(sz!=0)
	    {
	        int ck=sz;s++;sz=0;
	        for(int i=1;i<=ck;i++)
	        {
	            int temp=que.front();que.pop();
	            for(int j=1;j<=px[temp][0];j++)
	            {
	                p=px[temp][j];
	                indgr[p]--;
	                if(indgr[p]==0)
	                {
	                    sz++;
	                    que.push(p);
	                }
	            }
	        }
	    }
	    printf("%d\n",s);
	}
    return 0;
}

Pascal :

var n,m,i,j,k,s,x,max:longint;p:array[1..1010,1..1010]of boolean;
    d:array[1..1000]of boolean;kk,c,level:array[1..1010]of longint;
    a:array[0..1010]of longint;
begin
  read(n,m);
  for i:=1 to m do
    begin
      fillchar(d,sizeof(d),false);
      read(s);
      for j:=1 to s do
        begin
          read(c[j]);
          d[c[j]]:=true;
        end;
      for j:=c[1] to c[s] do
        if d[j]=false then
          begin
            for k:=1 to s do p[c[k],j]:=true;
          end;
    end;
  for i:=1 to n do
    begin
      for j:=1 to n do
        if p[j,i] then inc(kk[i]);
      if kk[i]=0 then
        begin
          inc(a[0]);
          a[a[0]]:=i;
        end;
    end;
  while a[0]>0 do
    begin
      x:=a[a[0]];
      dec(a[0]);
      for i:=1 to n do
        if p[x,i] then
          begin
            if level[x]>=level[i] then level[i]:=level[x]+1;
            dec(kk[i]);
            if kk[i]=0 then
              begin
                inc(a[0]);
                a[a[0]]:=i;
              end;
          end;
    end;
  for i:=1 to n do
    if level[i]>max then max:=level[i];
  writeln(max+1);
end.