text: from math import acos, pi, sqrt
  
  AB = int(input())
  BC = int(input())
  
  AC = sqrt((AB ** 2 + BC ** 2))
  
  MC = MB = AC / 2.0
  
  # Law of Cosines
  angle = acos((MB ** 2 + BC ** 2 - MC ** 2) / (2 * MB * BC))
  
  angle = int(round((180 * angle) / pi))
  
  print(f"{angle}°")
  