#include <bits/stdc++.h>
#define rep(x, l, r) for(int x = l; x <= r; x++)
#define repd(x, r, l) for(int x = r; x >= l; x--)
#define clr(x, y) memset(x, y, sizeof(x))
using namespace std;
typedef long long ll;
const int INF = 0x3f3f3f3f;

const int MAXN = 2e5 + 5;
const int MAXM = 25;
const int mod = 1e9 + 7;

int sum[MAXN][MAXM][MAXM], l[MAXN], r[MAXN];

int judge(int x, int y){
    int res = x ^ y;
    // printf("%d  %d  %d\n", x, y, res);
    repd(i, 20, 0){
        if((1 << i) & res) return i + 1;
    }
    return 0;
}

int main(){
    // rep(i, 1, 100){
    //     rep(j, i, 100) printf("%d ", judge(i, j));
    //     puts("");
    // }
    int t;
    scanf("%d", &t);
    while(t--){
        int n, m;
        scanf("%d%d", &m, &n);
        rep(i, 1, n){
            rep(j, 0, m + 1)
                rep(k, 0, m + 1) sum[i][j][k] = 0;
        }
        rep(i, 1, n){
            scanf("%d%d", &l[i], &r[i]);
        }
        rep(i, l[1], r[1]){
            int w = judge(i, l[2]), v = judge(i, r[1]);
            sum[1][w][v] = (sum[1][w][v] + i) % mod;
            // printf("%d 1 : %d  %d      %d\n", i, w, v, sum[1][w][v]);
        }
        l[n + 1] = 1 << m;
        rep(i, 2, n){
            rep(j, l[i], r[i]){
                int w0 = judge(j, l[i]), v0 = judge(j, r[i - 1]);
                int w1 = judge(j, l[i + 1]), v1 = judge(j, r[i]);
                // printf("%d : %d  %d\n", j, w0, v0);
                rep(p, w0, m + 1)
                    repd(q, v0, 0) sum[i][w1][v1] = (sum[i][w1][v1] + 1ll * sum[i - 1][p][q] * j % mod) % mod;
            }
        }
        int ans = 0;
        rep(j, 0, m + 1)
            rep(k, 0, m + 1) ans = (ans + sum[n][j][k]) % mod;
        printf("%d\n", ans);
    }
    return 0;
}