import math



a, b, x = list(map(int, input().split()))



p = ((x*2)/(a**2)) - b



if p == 0:

    print((45))

    exit()



if p > 0:

    radian = math.atan2(a, b-p)

    print((90-math.degrees(radian)))

else:

    p = 2*x/(a*b)

    radian = math.atan2(b, p)

    print((math.degrees(radian)))

import math



a, b, x = list(map(int, input().split()))



s = x / a



if s >= a * b / 2:

    h = (a * b - s) * 2 / a

    radian = math.atan2(h, a)

else:

    w = s * 2 / b

    radian = math.atan2(b, w)

ans = math.degrees(radian)

print(ans)

import math

a, b, x = list(map(int, input().split()))
p = ((x * 2) / (a**2)) - b
if p == 0:
    print((45))
    exit()
if p > 0:
    radian = math.atan2(a, b - p)
    print((90 - math.degrees(radian)))
else:
    p = 2 * x / (a * b)
    radian = math.atan2(b, p)
    print((math.degrees(radian)))

import math

a, b, x = list(map(int, input().split()))
s = x / a
if s >= a * b / 2:
    h = (a * b - s) * 2 / a
    radian = math.atan2(h, a)
else:
    w = s * 2 / b
    radian = math.atan2(b, w)
ans = math.degrees(radian)
print(ans)

-p = ((x * 2) / (a**2)) - b -if p == 0: -    print((45)) -    exit() -if p > 0: -    radian = math.atan2(a, b - p) -    print((90 - math.degrees(radian))) +s = x / a +if s >= a * b / 2: +    h = (a * b - s) * 2 / a +    radian = math.atan2(h, a) -    p = 2 * x / (a * b) -    radian = math.atan2(b, p) -    print((math.degrees(radian))) +    w = s * 2 / b +    radian = math.atan2(b, w) +ans = math.degrees(radian) +print(ans)