import sys, time
import decimal

# http://www.astromia.com/astronomia/nuestravia.htm
anioluz = decimal.Decimal("9.46e+15")  # en metros
radio_galaxia = 100000 * anioluz

# factorial, hecha por mi, a lo bruto
def fact(x):
    if x <= 1:
            return 1
    m = 2
    for i in xrange(3,x+1):
            m*= i
    return m

# formula de PI: http://www.cs.uwaterloo.ca/~alopez-o/math-faq/node38.html

k1 = 545140134
k2 = 13591409
k3 = 640320
k4 = 100100025
k5 = 327843840
k6 = 53360

# lo de adentro de la sumatoria
def sumatando(n):
    h2 = (-1)**n * fact(6*n) * (k2 + n * k1)
    h3 = fact(n)**3 * fact(3*n) * (8*k4*k5)**n
    res = decimal.Decimal(h2) / h3
    return res

# la sumatoria en forma de generador
def sumatoria(limite):
    n = 0
    while True:
        s = sumatando(n)
        yield s
        n += 1
        if n == limite:
            return

# calcula y devuelve pi
h1 = (k6 * decimal.Decimal(k3).sqrt())
def calcula(vueltas):
    tot = 0
    for x in sumatoria(vueltas):
        tot += x
    pi = h1 / tot
    return pi
    

def main():
    vueltas = 1
    pi_m1 = 0
    pi_m0 = 0
    while True:
        tini = time.time()
        pi = calcula(vueltas)
        demora = time.time() - tini
        print "%2d %.3f" % (vueltas, demora)
        if pi == pi_m0:
            print pi_m1
            print pi_m0
            perim_m1 = 2 * pi_m1 * radio_galaxia
            perim_m0 = 2 * pi_m0 * radio_galaxia
            print "dif", perim_m0 - perim_m1
            return
        pi_m1 = pi_m0
        pi_m0 = pi
        vueltas += 1

if __name__ == "__main__":
    if len(sys.argv) == 2:
        c = decimal.getcontext()
        c.prec = int(sys.argv[1])
    main()