mod = 1000000007
eps = 10**-5


def main():
    import sys
    from math import log
    input = sys.stdin.readline

    p, q = map(int, input().split())
    ok = 1
    ng = 10**18
    mid = (ok+ng) // 2
    while ng - ok > eps:
        if mid ** 2 < p + q * mid * log(mid, 2):
            ok = mid
        else:
            ng = mid
        mid = (ok+ng) / 2
    print(ok)


if __name__ == '__main__':
    main()