#include <bits/stdc++.h>
using namespace std;
using ll=long long;
const ll ILL=2167167167167167167;
const int INF=2100000000;
#define rep(i,a,b) for (int i=(int)(a);i<(int)(b);i++)
#define all(p) p.begin(),p.end()
template<class T> using _pq = priority_queue<T, vector<T>, greater<T>>;
template<class T> int LB(vector<T> &v,T a){return lower_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> int UB(vector<T> &v,T a){return upper_bound(v.begin(),v.end(),a)-v.begin();}
template<class T> bool chmin(T &a,T b){if(b<a){a=b;return 1;}else return 0;}
template<class T> bool chmax(T &a,T b){if(a<b){a=b;return 1;}else return 0;}
template<class T> void So(vector<T> &v) {sort(v.begin(),v.end());}
template<class T> void Sore(vector<T> &v) {sort(v.begin(),v.end(),[](T x,T y){return x>y;});}
bool yneos(bool a,bool upp=false){if(a){cout<<(upp?"YES\n":"Yes\n");}else{cout<<(upp?"NO\n":"No\n");}return a;}
template<class T> void vec_out(vector<T> &p,int ty=0){
    if(ty==2){cout<<'{';for(int i=0;i<(int)p.size();i++){if(i){cout<<",";}cout<<'"'<<p[i]<<'"';}cout<<"}\n";}
    else{if(ty==1){cout<<p.size()<<"\n";}for(int i=0;i<(int)(p.size());i++){if(i) cout<<" ";cout<<p[i];}cout<<"\n";}}
template<class T> T vec_min(vector<T> &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmin(ans,x);return ans;}
template<class T> T vec_max(vector<T> &a){assert(!a.empty());T ans=a[0];for(auto &x:a) chmax(ans,x);return ans;}
template<class T> T vec_sum(vector<T> &a){T ans=T(0);for(auto &x:a) ans+=x;return ans;}
int pop_count(long long a){int res=0;while(a){res+=(a&1),a>>=1;}return res;}
template<class T> T square(T a){return a * a;}

// https://259-momone.hatenablog.com/entry/2025/04/28/232456

struct F{
    ll mx = 0;
    ll sum = 0;
};

F op(F l, F r){
    chmax(l.mx, r.mx + l.sum);
    l.sum += r.sum;
    return l;
}

F e(){
    return F{};
}

F monoid_pow(F l, ll v){
    F res = e();
    while (v){
        if (v & 1) res = op(res, l);
        l = op(l, l);
        v /= 2;
    }
    return res;
}

F floor_prod(ll n, ll m, ll a, ll b, F x, F y) {
    // x *= monoid_pow(y, a / m);
    x = op(x, monoid_pow(y, a / m));
    a %= m;

    const auto prefix_prod = monoid_pow(y, b / m);
    b %= m;

    const auto y_max{(a) * n + b};
    if (y_max < m)
        return op(prefix_prod , monoid_pow(x, n));

    return op(op(prefix_prod , floor_prod((y_max / m) - 1, a, m, m + a - b - 1, y, x)), op(y, monoid_pow(x, (y_max % m) / a)));
}


void solve();
// POP'N ROLL MUSIC / TOMOO
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int t = 1;
    cin >> t;
    rep(i, 0, t) solve();
}

void solve(){
    ll N, M, A, B, C, D;
    cin >> N >> M >> A >> B >> C >> D;
    if (A >= 0 && B >= 0){
        cout << A * (N - 1) + B * ((C * (N - 1) + D) / M) << "\n";
    }
    else if (A <= 0 && B <= 0){
        cout << "0\n";
    }
    else if (A > 0 && B < 0){
        auto ans = floor_prod(N, M, C, D, {A, A}, {0ll, B});
        cout << ans.mx - A << "\n";
    }
    else{
        auto ans = floor_prod(N - 1, M, C, D, {0ll, A}, {B, B});
        cout << ans.mx << "\n";
    }
}