vector<int>pic[maxn];
int dfn[maxn],low[maxn],ans[maxn];
bool ins[maxn];
stack<int>st;
int dind=0,block=0;
int siz[maxn],cud[maxn];
void tarjan(int x)
{dind++;dfn[x]=low[x]=dind;ins[x]=true;st.push(x);for (int j=0;j<pic[x].size();j++){int y=pic[x][j];if (dfn[y]==0){tarjan(y);low[x]=min(low[x],low[y]);}else if (ins[y]) low[x]=min(low[x],dfn[y]);}if (low[x]==dfn[x]){block++;siz[block]=0;while (true){int thi=st.top();st.pop();ans[thi]=block;siz[block]++;ins[thi]=false;if (thi==x) break;}}
}

#include<iostream>
#include<cstdio>
#include<cstring>
#include<vector>
#include<stack>
using namespace std;
const int maxn=1010;
vector<int> pic[maxn],new_[maxn];
int dfn[maxn],low[maxn],ans[maxn];
bool ins[maxn];
stack<int>st;
int dind=0,block=0;
int siz[maxn],dp[maxn],Ans;
void tarjan(int x)
{dind++;dfn[x]=low[x]=dind;ins[x]=true;st.push(x);for (int j=0;j<pic[x].size();j++){int y=pic[x][j];if (!dfn[y]){tarjan(y);low[x]=min(low[x],low[y]);}else if (ins[y]) low[x]=min(low[x],dfn[y]);}if (low[x]==dfn[x]){block++;siz[block]=0;while (true){int thi=st.top();st.pop();ans[thi]=block;siz[block]++;ins[thi]=false;if (thi==x) break;}}
}
int DP(int x){    if(dp[x]!=-1) return dp[x];int Max=0;  for(int i=0;i<new_[x].size();i++)  Max=max(Max,DP(new_[x][i]));  return dp[x]=siz[x]+Max;
}
void init(int n){for(int i=1;i<=n;i++) pic[i].clear(),new_[i].clear();memset(dfn,0,sizeof(dfn)); memset(low,0,sizeof(low));memset(ans,0,sizeof(ans)); memset(ins,0,sizeof(ins));while(!st.empty()) st.pop(); dind=block=Ans=0;memset(siz,0,sizeof(siz)); memset(dp,-1,sizeof(dp));
}
int main(){int n,m,N,u,v;scanf("%d",&N);while(N--){scanf("%d%d",&n,&m);init(n);while(m--){scanf("%d%d",&u,&v);pic[u].push_back(v);}for(int i=1;i<=n;i++)if(!dfn[i]) tarjan(i);for(int i=1;i<=n;i++)for(int j=0;j<pic[i].size();j++)if(ans[i]!=ans[pic[i][j]]) new_[ans[pic[i][j]]].push_back(ans[i]);for(int i=1;i<=block;i++) Ans=max(Ans,DP(i));printf("%d\n",Ans);}return 0;
}

#include<iostream>
#include<cstdio>
#include<cstring>
#include<vector>
#include<stack>
#include<set>
using namespace std;
const int maxn=110;
vector<int> pic[maxn];
int dfn[maxn],low[maxn],ans[maxn];
bool ins[maxn];
stack<int>st;
set<int>check[maxn];
int dind=0,block=0;
int siz[maxn];
int ans1,in[maxn],out[maxn];void tarjan(int x)
{dind++;dfn[x]=low[x]=dind;ins[x]=true;st.push(x);for (int j=0;j<pic[x].size();j++){int y=pic[x][j];if (!dfn[y]){tarjan(y);low[x]=min(low[x],low[y]);}else if (ins[y]) low[x]=min(low[x],dfn[y]);}if (low[x]==dfn[x]){block++;siz[block]=0;while (true){int thi=st.top();st.pop();ans[thi]=block;siz[block]++;ins[thi]=false;if (thi==x) break;}}
}
int main(){int n,i,j;scanf("%d",&n);for(i=1;i<=n;i++){scanf("%d",&j);while(j) pic[i].push_back(j),scanf("%d",&j);  }for(int i=1;i<=n;i++)if(!dfn[i]) tarjan(i);for (i=1;i<=n;i++)for (j=0;j<pic[i].size();j++){int b1=ans[i],b2=ans[pic[i][j]];if (b1==b2) continue;if (check[b1].count(b2)) continue;check[b1].insert(b2);in[b2]++; out[b1]++;}int root=0,leaf=0;for(int i=1;i<=block;i++){if(!in[i]) root++;if(!out[i]) leaf++;}printf("%d\n",root);if(block==1) printf("0");else printf("%d",max(leaf,root));return 0;
}

#include<iostream>
#include "minmax.h"
#include<cstdio>
#include<cstring>
#include<vector>
#include<stack>
#include<set>
using namespace std;
const int maxn=20010;
vector<int> pic[maxn];
int dfn[maxn],low[maxn],ans[maxn];
bool ins[maxn];
stack<int>st;
set<int>check[maxn];
int dind=0,block=0,siz[maxn];
int in[maxn],out[maxn],T;
void tarjan(int x)
{dind++;dfn[x]=low[x]=dind;ins[x]=true;st.push(x);for (int j=0;j<pic[x].size();j++){int y=pic[x][j];if (!dfn[y]){tarjan(y);low[x]=min(low[x],low[y]);}else if (ins[y]) low[x]=min(low[x],dfn[y]);}if (low[x]==dfn[x]){block++;siz[block]=0;while (true){int thi=st.top();st.pop();ans[thi]=block;siz[block]++;ins[thi]=false;if (thi==x) break;}}
}
void init(int n){for(int i=1;i<=n;i++)  pic[i].clear(),check[i].clear();;memset(dfn,0,sizeof(dfn)); memset(low,0,sizeof(low));memset(ans,0,sizeof(ans)); memset(ins,0,sizeof(ins));while(!st.empty()) st.pop(); dind=0;block=0; memset(siz,0,sizeof(siz));memset(in,0,sizeof(in)); memset(out,0,sizeof(out));
}
int main(){scanf("%d",&T);while(T--){int n,i,j,m;scanf("%d%d",&n,&m);init(n);for(i=1;i<=m;i++){int x,y;scanf("%d%d",&x,&y);pic[x].push_back(y);    }for(int i=1;i<=n;i++)if(!dfn[i]) tarjan(i);for (i=1;i<=n;i++)for (j=0;j<pic[i].size();j++){int b1=ans[i],b2=ans[pic[i][j]];if (b1==b2) continue;if (check[b1].count(b2)) continue;check[b1].insert(b2);in[b2]++; out[b1]++;}int root=0,leaf=0;for(int i=1;i<=block;i++){if(!in[i]) root++;if(!out[i]) leaf++;}if(block==1) printf("0\n");else printf("%d\n",max(leaf,root));}return 0;
}