#####ejercicio 3
import math
# print "convertir angulos de radianes a grados"
# print "ingrese el valor en radianes"
# def angulo(grados):
# 	print angulo
# 	radianes=(radianes*math.pi)/180
# 	return (radianes)
# # print 'ingrese le valor en 'angulos'

# def grados(radianes):
# 	grados=(float(radianes)/math.pi)*180
# 	return grados
# # print 'ingrese le valor en radianes'
# # def radianes(grados):
# #    print grados
# #    radianes=math.acos(math.cos(math.pi(2))/math.pi
# #    return radianes
# print grados(raw_input())
# # print grados(math.pi)
# # print grados(math.pi/2)
# # print grados(math.pi/6)
# # print grados(180)
# # print grados(radianes(30))
# # print radianes(grados(math.pi))
# # print radianes(grados(math.pi/2))


print "ingrese el valor en grados"
def radianes(grados):
	radianes=(float(grados)*math.pi)/180
	return radianes
# print 'ingrese le valor en grados'
print radianes(raw_input())
# print grados(math.pi)
# print grados(math.pi/2)
# print grados(math.pi/6)
# print grados(180)
# print grados(radianes(30))
# print radianes(grados(math.pi))
# print radianes(grados(math.pi/2))
