#include<stdio.h>
#include<algorithm>
#include<string.h>
#include<math.h>
#include<string>
#include<iostream>
#include<queue>
#include<stack>
#include<map>
#include<vector>
#include<set>
using namespace std;
typedef long long LL;
#define mid (L+R)/2
#define lson rt*2,L,mid
#define rson rt*2+1,mid+1,R
#pragma comment(linker, "/STACK:102400000,102400000")
const int maxn = 1e5+300;
const int INF = 0x3f3f3f3f;
typedef long long  LL;
typedef unsigned long long ULL;
priority_queue<int>PQ;
queue<int>Q;
int ind[maxn];
vector<int> G[maxn];
int main(){
    int T, n, m;
    scanf("%d",&T);
    while(T--){
        scanf("%d%d",&n,&m);
        int u, v;
        for(int i = 1; i <= n; i++){
            G[i].clear();
        }
        memset(ind,0,sizeof(ind));
        for(int i = 1; i <= m; i++){
            scanf("%d%d",&u,&v);
            ind[v]++;
            G[u].push_back(v);
        }
        for(int i = 1; i <= n; i++){
            if(ind[i] == 0){
                PQ.push(i);
            }
        }
        int Min = INF;
        LL ans = 0;
        while(!PQ.empty()){
            int u = PQ.top(); PQ.pop();
            Min = min(Min, u);
            ans += Min;
            for(int j = 0; j < G[u].size(); j++){
                int &v = G[u][j];
                ind[v]--;
                if(ind[v] == 0){
                    PQ.push(v);
                }
            }
        }
        printf("%lld\n",ans);
    }
    return 0;
}