INF = 10**2000
def solve():
    n, m, a, b, c, d = map(int, input().split())
    def eval(m, a, b, c, d, x: int) -> int:
        return a * x + b * ((c * x + d) // m)
    def f(n, m, a, b, c, d: int) -> int:
        if n <= 0: return -INF
        if c < 0 or d < 0:
            return f(n, m, a + b * (c // m), b, c % m, d % m) + b * (d // m)
        if a >= 0 and b >= 0: return eval(m, a, b, c, d, n-1)
        if a < 0 and b < 0: return eval(m, a, b, c, d, 0)
        if m == 1:
            return max(eval(m, a, b, c, d, 0), eval(m, a, b, c, d, n-1))
        if c >= m:
            c1 = c // m
            c2 = c % m
            return f(n, m, a + b * c1, b, c2, d)
        if d >= m:
            d1 = d // m
            d2 = d % m
            return f(n, m, a, b, c, d2) + b * d1
        k = (c * (n-1) + d) // m
        if a < 0:
            ans = f(k, c, b, a, m, m - d + c - 1) + b
            return max(ans, eval(m, a, b, c, d, 0))
        ans = f(k, c, b, a, m, m - d - 1)
        return max(ans, eval(m, a, b, c, d, n-1))
    ans = f(n, m, a, b, c, d)
    print(ans)

t = int(input())
for _ in range(t):
    solve()