#include<cstdio>

 #include<string>

 #include<set>

 #include<vector>

 #include<queue>

 #include<functional>

 using namespace std;

 #define MAX 100010

 int InDeg[MAX];

 int n, m, Count;

 int Ans[MAX];

 vector<int> v[MAX];

 void TopoSort()

 {

     priority_queue<int> PQ;

     for(int i=n; i>=; i--) //找出入度为0的点并放入优先队列

         if(InDeg[i]==) PQ.push(i);

     while(!PQ.empty()) //BFS

     {

         int Tmp = PQ.top();

         PQ.pop();

         Ans[Count++] = Tmp;

         for(int i=; i<v[Tmp].size(); i++)

         {

             InDeg[v[Tmp][i]]--;

             if(InDeg[v[Tmp][i]]==) PQ.push(v[Tmp][i]);

         }

     }

 }

 int main()

 {

     int x, y,t;

     scanf("%d",&t);

     while(t--)

     {

         scanf("%d%d",&n,&m);

         for(int i=;i<=n;i++)v[i].clear(),InDeg[i]=;

         Count = ;

         for(int i=; i<m; i++)

         {

             scanf("%d%d",&x,&y);

             InDeg[y]++;

             v[x].push_back(y);

         }

         TopoSort();

         int min=;

         long long an=;

         for(int i=; i<Count; i++){

             min=min>Ans[i]?Ans[i]:min;

             an+=min;

         }

         printf("%I64d\n",an);

     }

 }