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#include <bits/stdc++.h>
using namespace std;
#define inf 0x3f3f3f3f
const int N = 510;
int n, m, x, y, ans;
int g[N][N];
void floyd() {
for (int k = 1; k <= n; k++)
for (int i = 1; i <= n; i++) {
if (!g[i][k]) continue; // floyd优化
for (int j = 1; j <= n; j++)
g[i][j] |= g[i][k] & g[k][j]; // 通过k传递,或运算
}
}
int main() {
int T;
cin >> T;
while (T--) {
cin >> n >> m;
memset(g, 0, sizeof g);
while (m--) {
cin >> x >> y;
g[x][y] = 1; // x<y
}
// 计算传递闭包
floyd();
ans = 0;
for (int i = 1; i <= n; i++) // 统计答案
for (int j = i + 1; j <= n; j++)
if (!g[i][j] && !g[j][i]) ans++; // 无法确定大小关系
cout << ans << endl;
}
return 0;
}