import math

def main():
    import sys
    A, B = map(int, sys.stdin.readline().split())
    a = abs(A)
    b = abs(B)
    d = math.gcd(a, b)
    
    sum_total = 0.0
    s = 0
    while True:
        denominator_base = 2 + d * s
        exponent = denominator_base
        current_term = (s + 1) / (denominator_base ** exponent)
        if current_term < 1e-30:  # Break when terms are negligibly small
            break
        sum_total += current_term
        s += 1
    
    # Ensuring sufficient precision in output
    print("{0:.12f}".format(sum_total))

if __name__ == '__main__':
    main()