#! /usr/bin/python

import sys
import random as rd
from string import ascii_lowercase as beta
from string import ascii_uppercase as alfa


def passgen(longu):
    colection = ""
    caracters = "?/.+@/#%".replace("", " ").split()
    for i in range(longu):
        des = rd.randrange(1, 101)
        if des < 40:
            colection += str(rd.randrange(1, 10))
        elif des < 60:
            x = rd.randrange(0, len(caracters))
            colection += caracters[x]
        elif des < 80:
            colection += alfa[rd.randrange(0, len(alfa))]
        else:
            colection += beta[rd.randrange(0, len(beta))]
    return colection


def main():
    longitud = len(sys.argv)
    if longitud == 1:
        print "Clave de 8 caracteres por defecto generada"
        print passgen(8)
    elif longitud == 2:
        x = int(sys.argv[1])
        print "clave de %d caracteres generada" % x
        print passgen(x)
    else:
        print "La sintaxis debe ser passgen [longitud de contrasena]"


main()