My solution:

include

using namespace std;

int main(){ ios::sync_with_stdio(0); cin.tie(0);

int n, q;
cin >> n >> q;
vector<vector<int>> no(n);
for(int i = 0; i<n; i++){
    int k;
    cin >> k;
    no[i].resize(k);
    for(int j = 0; j<k; j++){
        cin >> no[i][j];
    }
}
while(q-->0){
    int x, y;
    cin >> x >> y;
    cout << no[x][y] << '\n';
}

return 0;

}

I am not that familiar with pointers actually, so I used vectors instead.

return 0;

}