import sys

from io import StringIO

import unittest

import math





def resolve():

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



    tan_theta = 2*(b/a-x/math.pow(a, 3))

    tan_theta2 = a * pow(b, 2) / (2 * x)



    if math.pow(a, 3) / 2 * tan_theta < x:

        theta = math.atan(tan_theta)

    else:

        theta = math.atan(tan_theta2)



    print((math.degrees(theta)))





class TestClass(unittest.TestCase):

    def assertIO(self, input, output):

        stdout, stdin = sys.stdout, sys.stdin

        sys.stdout, sys.stdin = StringIO(), StringIO(input)

        resolve()

        sys.stdout.seek(0)

        out = sys.stdout.read()[:-1]

        sys.stdout, sys.stdin = stdout, stdin

        self.assertEqual(out, output)



    def test_入力例_1(self):

        input = """2 2 4"""

        output = """45.0000000000"""

        self.assertIO(input, output)



    def test_入力例_2(self):

        input = """12 21 10"""

        output = """89.7834636934"""

        self.assertIO(input, output)



    def test_入力例_3(self):

        input = """3 1 8"""

        output = """4.2363947991"""

        self.assertIO(input, output)





if __name__ == "__main__":

    # unittest.main()

    resolve()

# https://atcoder.jp/contests/abc144/tasks/abc144_d

import math



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

if a * a * b * (1/2) <= x:

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

    print((math.degrees(math.atan(tmp))))

else:

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

    print((math.degrees(math.atan(tmp))))

import sys
from io import StringIO
import unittest
import math


def resolve():
    a, b, x = list(map(int, input().split()))
    tan_theta = 2 * (b / a - x / math.pow(a, 3))
    tan_theta2 = a * pow(b, 2) / (2 * x)
    if math.pow(a, 3) / 2 * tan_theta < x:
        theta = math.atan(tan_theta)
    else:
        theta = math.atan(tan_theta2)
    print((math.degrees(theta)))


class TestClass(unittest.TestCase):
    def assertIO(self, input, output):
        stdout, stdin = sys.stdout, sys.stdin
        sys.stdout, sys.stdin = StringIO(), StringIO(input)
        resolve()
        sys.stdout.seek(0)
        out = sys.stdout.read()[:-1]
        sys.stdout, sys.stdin = stdout, stdin
        self.assertEqual(out, output)

    def test_入力例_1(self):
        input = """2 2 4"""
        output = """45.0000000000"""
        self.assertIO(input, output)

    def test_入力例_2(self):
        input = """12 21 10"""
        output = """89.7834636934"""
        self.assertIO(input, output)

    def test_入力例_3(self):
        input = """3 1 8"""
        output = """4.2363947991"""
        self.assertIO(input, output)


if __name__ == "__main__":
    # unittest.main()
    resolve()

# https://atcoder.jp/contests/abc144/tasks/abc144_d
import math

a, b, x = list(map(int, input().split()))
if a * a * b * (1 / 2) <= x:
    tmp = 2 * (a * a * b - x) / (a * a * a)
    print((math.degrees(math.atan(tmp))))
else:
    tmp = a * b * b / (2 * x)
    print((math.degrees(math.atan(tmp))))

-import sys -from io import StringIO -import unittest +# https://atcoder.jp/contests/abc144/tasks/abc144_d - -def resolve(): -    a, b, x = list(map(int, input().split())) -    tan_theta = 2 * (b / a - x / math.pow(a, 3)) -    tan_theta2 = a * pow(b, 2) / (2 * x) -    if math.pow(a, 3) / 2 * tan_theta < x: -        theta = math.atan(tan_theta) -    else: -        theta = math.atan(tan_theta2) -    print((math.degrees(theta))) - - -class TestClass(unittest.TestCase): -    def assertIO(self, input, output): -        stdout, stdin = sys.stdout, sys.stdin -        sys.stdout, sys.stdin = StringIO(), StringIO(input) -        resolve() -        sys.stdout.seek(0) -        out = sys.stdout.read()[:-1] -        sys.stdout, sys.stdin = stdout, stdin -        self.assertEqual(out, output) - -    def test_入力例_1(self): -        input = """2 2 4""" -        output = """45.0000000000""" -        self.assertIO(input, output) - -    def test_入力例_2(self): -        input = """12 21 10""" -        output = """89.7834636934""" -        self.assertIO(input, output) - -    def test_入力例_3(self): -        input = """3 1 8""" -        output = """4.2363947991""" -        self.assertIO(input, output) - - -if __name__ == "__main__": -    # unittest.main() -    resolve() +a, b, x = list(map(int, input().split())) +if a * a * b * (1 / 2) <= x: +    tmp = 2 * (a * a * b - x) / (a * a * a) +    print((math.degrees(math.atan(tmp)))) +else: +    tmp = a * b * b / (2 * x) +    print((math.degrees(math.atan(tmp))))