import copy
import heapq
import itertools
import math
import operator
import sys
from bisect import bisect, bisect_left, bisect_right, insort
from collections import Counter, deque
from fractions import Fraction
from functools import cmp_to_key, lru_cache, partial
from inspect import currentframe
from math import ceil, gcd, log10, pi, sqrt

# import pypyjit
# pypyjit.set_param('max_unroll_recursion=-1')
input = sys.stdin.readline
sys.setrecursionlimit(10000000)
# mod = 10 ** 9 + 7
mod = 998244353
# mod = 1 << 128
# mod = 10 ** 30 + 1
INF = 1 << 61
DIFF = 10 ** -9
DX = [1, 0, -1, 0, 1, 1, -1, -1]
DY = [0, 1, 0, -1, 1, -1, 1, -1]

def read_values(): return tuple(map(int, input().split()))
def read_index(): return tuple(map(lambda x: int(x) - 1, input().split()))
def read_list(): return list(read_values())
def read_lists(N): return [read_list() for _ in range(N)]
def dprint(*values): print(*values, file=sys.stderr)
def dprint2(*values):
    names = {id(v): k for k, v in currentframe().f_back.f_locals.items()}
    dprint(", ".join(f"{names.get(id(value), '???')}={repr(value)}" for value in values))


def solve():
    N, M, A, B, C, D = read_values()

    def v(x):
        return A * x + B * ((C * x + D) // M)


    def f(N, M, A, B, C, D, K):

        assert(0 <= C < M)
        assert(0 <= D < M)
        if N == 0:
            return 0

        def v(x):
            return A * x + B * ((C * x + D) // M) + K

        # ans = max(v(i) for i in range(N))
        # print(f"{N=}, {M=}, {A=}, {B=}, {C=}, {D=}, {K=}: {ans=}")

        if C == 0:
            return max(v(0), v(N - 1))

        res = 0
        k_max = (C * (N - 1) + D) // M  # kの範囲は [0, k_max]

        # k = 0 となるような場合、 x \in [0, min((M - D) / C, N)) での最大値を求める
        l = 0
        r = min((M - D + C - 1) // C, N)
        res = max((res, v(l), v(r - 1)))

        # k = k_max となるような場合、 x \in [(M * k_max - D) / C, min((M * (k_max + 1) - D) / C) ,N)) での最大値を求める
        l = (M * k_max - D + C - 1) // C
        r = min((M * (k_max + 1) - D + C - 1) // C, N)
        res = max((res, v(l), v(r - 1)))

        # 端ではない部分は再帰で答えを求める。k は [l, r) の範囲なので、どうにかこうにかして [0, r - l) として求める
        l = (D + M - 1) // M
        r = (C * N + D) // M 
        # print(f"{l=}, {r=}")
        if l < r:
            m = M // C
            mr = M % C
            T = -D + C - 1 + mr * l + (0 if A < 0 else M)
            t = T // C
            tr = T % C
            A2 = m * A + B
            B2 = A
            C2 = mr
            D2 = tr
            K2 = K + l * (m * A + B) + A * t - (0 if A < 0 else A)
            M2 = C
            res = max(res, f(r - l, M2, A2, B2, C2, D2, K2))
        return res
    
    res = f(N, M, A, B, C, D, 0)
    # ans = max(v(i) for i in range(N))
    # print(f"{res=}, {ans=}")
    return res


def main():
    T = int(input())
    res = []
    for _ in range(T):
        res.append(solve())
    print(*res, sep="\n")


if __name__ == "__main__":
    main()