# calc sum_{i=0}^{n-1} floor((ai + b) / m)
def floor_sum(n, m, a, b)
    x = 0
    while n > 0
        if a >= m || a < 0
            q, a = a.divmod(m)
            x += n * (n - 1) / 2 * q
        end
        if b >= m || b < 0
            q, b = b.divmod(m)
            x += n * q
        end
        n, b = (a * n + b).divmod(m)
        m, a = a, m
    end
    x
end

def solve(n, d, m, s)
    pow2s, dm = 1 << s, d * m
    if pow2s != dm
        n = [n, d * pow2s / (pow2s - dm).abs].min
        n -= (floor_sum(n + 1, pow2s, m, 0) - floor_sum(n + 1, d, 1, 0)).abs
    end
    return n
end

for _ in 1..gets.to_i
    n, d, m, s = gets.split.map &:to_i
    puts solve(n, d, m, s)
end