# calc sum_{i=0}^{n-1} floor((ai + b) / m)
def floor_sum_unsigned(n: int, m: int, a: int, b: int) -> int:
    assert n >= 0 and m > 0 and a >= 0 and b >= 0
    ans = 0
    while True:
        if a >= m:
            ans += (n * (n - 1) >> 1) * (a // m)
            a %= m
        if b >= m:
            ans += n * (b // m)
            b %= m
        y_max = a * n + b
        if y_max < m: return ans
        n, b, m, a = y_max // m, y_max % m, a, m

def solve(n: int, d: int, m: int, s: int) -> int:
    assert n >= 0 and d > 0 and m >= 0 and s >= 0
    pow2s, dm = 1 << s, d * m
    if pow2s != dm:
        n = min(n, d * pow2s // abs(dm - pow2s))
        n -= abs(floor_sum_unsigned(n + 1, pow2s, m, 0) - floor_sum_unsigned(n + 1, d, 1, 0))
    return n

for _ in range(int(input())):
    n, d, m, s = map(int, input().split())
    print(solve(n, d, m, s))