from math import pi, sin, cos, tan

EPS = 0.0000000001



def f(a, b, theta):

    if theta > pi * 0.5 - EPS:

        ret = 0.0

    elif a * tan(theta) <= b:

        ret = a**2 * b - a**3 * tan(theta) * 0.5

    else:

        ret = a * b**2 * 0.5 / tan(theta)



    return ret



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



ok = pi * 0.5

ng = 0.0

while ok - ng >= EPS:

    mid = (ok + ng) * 0.5

    if f(a, b, mid) < x:

        ok = mid

    else:

        ng = mid

print(("{:.10f}".format(ok / pi * 180)))

from math import pi, tan

EPS = 0.0000000001



def f(a, b, theta):

    if theta > pi * 0.5 - EPS:

        ret = 0.0

    elif a * tan(theta) <= b:

        ret = a**2 * b - a**3 * tan(theta) * 0.5

    else:

        ret = a * b**2 * 0.5 / tan(theta)



    return ret



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



ok = pi * 0.5

ng = 0.0

while ok - ng >= EPS:

    mid = (ok + ng) * 0.5

    if f(a, b, mid) < x:

        ok = mid

    else:

        ng = mid

print(("{:.10f}".format(ok / pi * 180)))

from math import pi, sin, cos, tan

EPS = 0.0000000001


def f(a, b, theta):
    if theta > pi * 0.5 - EPS:
        ret = 0.0
    elif a * tan(theta) <= b:
        ret = a**2 * b - a**3 * tan(theta) * 0.5
    else:
        ret = a * b**2 * 0.5 / tan(theta)
    return ret


a, b, x = list(map(int, input().split()))
ok = pi * 0.5
ng = 0.0
while ok - ng >= EPS:
    mid = (ok + ng) * 0.5
    if f(a, b, mid) < x:
        ok = mid
    else:
        ng = mid
print(("{:.10f}".format(ok / pi * 180)))

from math import pi, tan

EPS = 0.0000000001


def f(a, b, theta):
    if theta > pi * 0.5 - EPS:
        ret = 0.0
    elif a * tan(theta) <= b:
        ret = a**2 * b - a**3 * tan(theta) * 0.5
    else:
        ret = a * b**2 * 0.5 / tan(theta)
    return ret


a, b, x = list(map(int, input().split()))
ok = pi * 0.5
ng = 0.0
while ok - ng >= EPS:
    mid = (ok + ng) * 0.5
    if f(a, b, mid) < x:
        ok = mid
    else:
        ng = mid
print(("{:.10f}".format(ok / pi * 180)))

-from math import pi, sin, cos, tan +from math import pi, tan