#! /usr/bin/env python3

import sys
import collatz

usage='usage: collatzSearch [digits] ([startDigits]) outputs the lenght of the collatz sequence for every number less than 10^digits, starting with 10^startDidgits.'

nextNumber = 1

if len(sys.argv)<2:
    print(usage)
    sys.exit()
digits = sys.argv[1]

try:
    digits = int(digits)
except:
    print(usage)
    sys.exit()
if len(sys.argv)>=3:
    try:
        nextNumber = 10**int(sys.argv[2])
    except:
        print(usage)
        sys.exit()

maxNumber = 10**digits

while nextNumber<maxNumber:
    print('collatz length of '+str(nextNumber)+' is: \n'+str(collatz.seqenceLength(nextNumber)))
    nextNumber += 1