import math

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

v=a*a*b

if v <= 2*x:

    b1=(v-x)/a*2/a

    c=math.sqrt(a**2+b1**2)

    print((math.degrees(math.acos(a/c))))

else:

    a1=((x/a)*2)/b

    c=math.sqrt(a1**2+b**2)

    print((math.degrees(math.asin(b/c))))

import math

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

if a*a*b <= 2*x:

    b1=(a*a*b-x)/a*2/a

    print((math.degrees(math.atan(b1/a))))

else:

    a1=((x/a)*2)/b

    print((math.degrees(math.atan(b/a1))))
import math

a, b, x = list(map(int, input().split()))
v = a * a * b
if v <= 2 * x:
    b1 = (v - x) / a * 2 / a
    c = math.sqrt(a**2 + b1**2)
    print((math.degrees(math.acos(a / c))))
else:
    a1 = ((x / a) * 2) / b
    c = math.sqrt(a1**2 + b**2)
    print((math.degrees(math.asin(b / c))))

import math

a, b, x = list(map(int, input().split()))
if a * a * b <= 2 * x:
    b1 = (a * a * b - x) / a * 2 / a
    print((math.degrees(math.atan(b1 / a))))
else:
    a1 = ((x / a) * 2) / b
    print((math.degrees(math.atan(b / a1))))

-v = a * a * b -if v <= 2 * x: -    b1 = (v - x) / a * 2 / a -    c = math.sqrt(a**2 + b1**2) -    print((math.degrees(math.acos(a / c)))) +if a * a * b <= 2 * x: +    b1 = (a * a * b - x) / a * 2 / a +    print((math.degrees(math.atan(b1 / a)))) -    c = math.sqrt(a1**2 + b**2) -    print((math.degrees(math.asin(b / c)))) +    print((math.degrees(math.atan(b / a1))))