#!/usr/bin/env python3
from fractions import Fraction
def dir(v, t):
    x = v * t % 2
    return x < 1
def pos(v, t):
    x = v * t % 2
    return min(x, 2 - x)
v1 = Fraction(2, int(input()))
v2 = Fraction(2, int(input()))
v3 = Fraction(2, int(input()))
t = Fraction(0)
while t == 0 or not (pos(v1, t) == pos(v2, t) == pos(v3, t)):
    assert pos(v1, t) == pos(v2, t)
    if dir(v1, t) == dir(v2, t) == True: # right
        l = 2 * (1 - pos(v1, t))
    elif dir(v1, t) == dir(v2, t) == False: # left
        l = 2 * pos(v1, t)
    else:
        l = 2
    t += l / (v1 + v2)
print(t)