import math
print 'convertir angulos de radianes a grados'
# print 'ingrese el valor en radianes'
# def grados(rad):
# 	print  grados
# 	g=((rad)/math.pi)*180
# 	return g
print 'ingrese el valor en grados'
def radianes(g):
   	rad= (float(g)/180)*math.pi
   	return rad
# print grados(rad)
print radianes(raw_input())
# print grados(pi)
# print grados(pi/2)
# print grados(pi/6)
# print radianes(180)
# print radianes(360)
# print grados(radianes(180))
# print grados(radianes(30))
# print radianes(grados(pi))
# print radianes(grados(pi/2))
