import sys
input = sys.stdin.readline

def mwf(n: int, m: int, a: int, b: int, c: int, d: int) -> int:
    """ mwf(n,m,a,b,c,d) = max{ a*x+b*floor((c*x+d)/m) | 0 <= x < n} """
    a += c // m * b
    s = d // m * b
    c %= m
    d %= m
    y = (c * ~-n + d) // m
    r = max(s, s + a * ~-n + b * y)
    if y * a * b < 0:
        r = max(r, s + (a + b) * (a < 0) + mwf(y, c, b, a, m, m + ~d))
    return r

if __name__ == "__main__":
    for _ in range(int(input())):
        n, m, a, b, c, d = map(int, input().split())
        print(mwf(n, m, a, b, c, d))