Code Explanation for J7 (The Best Box - Practice(easy)) @cathoderay

Hi,
I tried to figure it out, but I didn’t get. can any one explain this code. what exactly doing.

p, s = map(int, input().split())  
x = (-p/2.0 + math.sqrt(p*p/4.0 - 6.0*s))/-6.0  
z = p/4.0 - 2*x  
print(round(x*x*z, 2))

It’s about logic, what he/she righten. [click here for orginal code](It’s about logic, what he/she righten. click here for orginal code)