d6.py

def fetch_input(file) -> str:
    ''' Fetches the txt file input for the current challenge '''

    with open(file, 'r') as file:
        data = file.read().replace('\n', '')

    return data

def check_start_of_packet(txt,window_length) -> bool:
    ''' Determine if current text is all unique characters '''
    
    if len(set(txt)) == window_length:
        return True
    
    return False

def check_all_input(data, window_length) -> int:
    ''' Returns the index where text is all different '''
    n = len(data)
    for i in range(0,n-window_length):
        subset = data[i:i+window_length]
        if check_start_of_packet(subset, window_length):
            return i+window_length
    
    return None

file = 'd6_input.txt'
data = fetch_input(file)

part1_window = 4
part2_window = 14

print("The start of packet is {} for part 1".format(check_all_input(data, part1_window)))
print("The start of packet is {} for part 2".format(check_all_input(data, part2_window)))

d6_input.txt

pjbjvjtjljplppjssvtvwtwptptztltbtrrjgrjrzrqrjrbrhbrhrlllbpbdbbzqqgsqshqssjjbsjbsbmbhhmchhrqrcqqbwbqwwqrrznnsbswwwdjwdwmmsvszzlbbgddbgdgfgttzjzrjzrjzzvrvqqgpqggtbgtgvvrhvhtvtjjbpjjfjhjbhbddbjjjmzmtmgmpgmmmljlnljjmpmbpmbmrrlhhlppdgdfgfbbqlbbtffjjgvvnpvpbpttqmmnhhgfgrrwhrrbnbznzccmbmvmmzszsvsbvbccsrslsjsbbtdtwtvttvpvzzvbzzwczwcczhzhwhjhjghgppgpgttdwdhwhphnppqmpqqhthcchdhmhnnbcnbcbbggbfblljttwsswspsggpjjzszcscsmcmdmnngzzhrzrbrhbhzbzvzgvgffnlnljlrrhchhsvhssmpmccncdnccgdgbglgtlggnllsvvpfvpfpbffsgglddjrrzzphhptprtppwrwffzllrbrmrpmpdmpdmpplpspcphcphhgmmqnmmvnmmdvmvsmmqjmmlmlbmlbmlltlptphpnncscbscbcggwhhgjgqjqmjmdjmdjdrrvgvvzlldgdnnvttmmpffdjjvvchcwwbhwbwzzlmlccrttcntccpcgccpgcpggdrrbtrthhlrrbqrrpspdsdldbldblbzbpbgggtngtgqqtwwdjjmmcrmcrcvclcddhllpzpdzzmccrtccfvffccfhccpscctbbbzqzvvllgwlgwgvwwjswjswsvvwhhvjvsjvjmmjhjrhrmrvrnrccmnmzzmdzzbtbvbqvvgzgcgvvvvlltvllbfbqqrppwhpwpffzddzdzwdzzrggmhmfhmhbbzjzsjzzhhjdhhdnndsnssnfffbmffwhwrhhmmbnnbrnrbrrtqtztnzzzzblbhbdhbbfmfqfmmsgszzvfzfmfwfnwfwggwngnqnwqnwqwvwqvwvdvrvjjfnjnmnfmmwzzltztjjqnnnmlmzlmmrcmclcqqhrhdhccdfdvfvccvtcvvdmmtmccwjjcbcrrjmrjrdrffgwwvbvlvsspwpsspzsschssmqsqmqmlqmmqgqfqcqjcjtthjttlddfvvwwjvvtpvvfsvffqnffznzqzszgzmmjttwztwzzhqqccqsqmqnmqqjhqhzhwhvhdddsndsdfftvffwlwnnmmdpmmnhhrqrrclcdlcddhcdcppgrprnpnptnpphgpbqfngdgzvgndwcgrwcsfmhzsvddhzbgjmvvdjjzswvgnpmvgdpwsgbgjzjpsrfdzdzjzzrpplbhsmgddqzjbdzdzltqqwqjzqvwfmcdppbdbprrwzhmnrqclzrnmdjnfbwmvdrwtpwvgscrqgpndqnzbjsbljcbthbpgdjdcdwfhpvjnbsfjdlrjldvvmtfdslrhlfwmvclqrljrqmmjgqfwmfgwdjzzptgcthvtgdswsqjrqvnzmtqldjjcqnfhtvbwhjqlvpptfwjrdpcwvzddgcjzvqbhtsnnnjqqmqlbgvqmvjhvvpbzcbdmhgmcjbfcccsvlzjztvjzrrlhtgwccdcgcptqlmdhmdhvqzfntbjqtsmvqgwsltqntgszllntrljfgfsghtbbcqrdgwqphmbqtzmjqccrgvqpqpchzjstdmmtvntwjqsbcqjgnhzlllcfbpgtgrhwwhqqdlgrlsbzbmchvjnsgpdnmqvtgwqjpgflqgfngjfcfwqzmvvgzmmhbgfnbzvzclwclqdcccgbrrzpwdtprgsvhbgsnbntgrvnzhrnzfzdmnlbnrbqvmjbwpgvjlhbcvsrlqmcsnlrvtfdwtvcbmlndgbctsnmtctjszlpddqmzbtphhhfznwbdfsgppmdmczmhmmrzpllfqqbgvlsrscpfgznhdhgrnnnvrchgvzlqbgvcfghjvlvrvpclfcshbmvglcfrjbzrbcjmjjrfgqthwfrqbgtjldmbnfwllspmwrvstvrltvrlvrtjvprgtgzjlrgclvjhqpfcwcdbdtzwdsdfrtsvtvgjmsszdfqlmhqqlzswjfndswlmhcrhglphvpnfjpbmggbwlmzjchpnrllbjpmgmzjjrqpqgsbrszqhdljcpnclvrvbntgtcdcmhtdhgslhpvdjpvrszfrjhsbvcvtfwvvgczprnpbhmnnlmctbtqdjspgvhvnhwvspwgnjvzllwlnjhfjwsslppmjbfbdnthcpzbcmnnbvhctgwgdvhvlrbltmdnlfcsncqgrmjprshdvvtvcccgzhszcjgczhmhtvmccjpchqshhdzjjhbfpzqdjszdhdvlmgctmwcjprwlsqbcqhlcrfdgnqzfdfvqslmqlppbsvbmjmfbrtdmpmtqvwvppcfzddjzhhzlrrnnhbrlhmzlqwftprfvctnfhfhfzrnrvggfqmqwcwszhtbfjncprgwcqbjlvtnrprlwwghswvprjmsbmqvwnnfggprndvshfvvwtrqjpwghgbppftgzhqjslfzhngwfsjnmjzdsjqgpmglwnjlcgmczgvndszrszcpnzqpbzjmgrfsbjlghwrbqsqdhlnhzsvsgbqhbcdffjlgrbdrrjvclzqpftlhdvvcrvlgvlpnjcqdcbdjtlwnldjhhhzrwsqlhlsztwrznfsszptlrhjmqwmnfwjtjwmmmtvwzhpmjgzgsscbddgvvhpcnhvnggzhbzvvjlmdftpbcsvtsttrvgghptmmcdclbdvmnsdntthfbdznbclwccnlzcvdwzrqgddjszvbdqcjppzrtpnrhfcvvwpjqczgqwzzzvzmlnlzqszvtllftthgwgftjzsndpzzcnqpcvmsdvvfrjdsvfclsqqhsjrrctfvdrlhfmhprjggdcmqrrbqtwnrllhhztvjgmzqszbvqfwsgllvhsvfrjffvdscwjzqlzlwdpgthddpgzjfdbdqpsnntwpslvsdpqfnsgcllszcjwvtqhwhpfrlfdgwrfmgfpjmvnstrmtfcvgwlqdfqvntltqtrmjjtwcthvwntqgvncssplnmvlnstlcphvlcmvjnstwldtntchcbmzmlzhgjfbrdlgzvqpgcndmfdnmcnwhmpdnpqstfddddcrpgrpfwfbzjqtnzwwqpzrqpmrjpfznrndfgwhtlvrcrphqfjzjbttwhgnsngqwvnsbvcqtjlmhvmnmnnmjcmlpnpgmrqsbmgljvsfqvrlljqzmzqqbgpvcrwdjmgsglssjswmnvtshhfqjhqmfmvcjwfpwsppgtrqsbhhcdljnjphnjszqpvdplbwzpwmmpwfhmhngtllzqvpmgdctmfqwwqjszssmjhwnrjdtmmvpdnwlqtcbpfcmwtbjmmsmmdpqgzdhsblgjmjbpzgqvqhnggtwmhztbbhlflllgwblncjjsngdgvsfdmsbsvlpnjjzqqbzhsqclmjnnmmwlpvtgwqmcgmrqdwdddlgbvhntbztbjnqhdlggnzwsdtdzprgddhtcttjrcpszgchtfwqjsdlnbntfwqpzpfsqrqjhthmcfszwtwcqwbvfzdnrrpmzjdrhsgmhfbsldvcrjdwvpqpszzlvbptljgvccqsdhhnztjpghbvhfptgplqdvldjzfthpspwvgljwnnndwrqzbrstnqbvrrcghssnrpvtrhmvcmbngwndzfswmgjwnnzqdcjhpthcgvthsnwqzrnzrvdjmctchhsbnrtvctzqfpcjhzmhnfjlqftbjztfbcppgmwvrzzrvlcpnpwwpvtcpdplrcfpgfqjtlfjtphhpcltwqcbqbznbtjrtdrpgtvzmgsclhpptrssqqbctdrftqzmwjmrmjtgmjmsnbnspjvcqpqnmgzgjrmfhghvsfsdqnbdjsbcpczsdswdcvhfzlgpzbtmztcnbpcvjnlcdmmlbtwzsfqtfnlrwjtwmgslcgptgbdsfwdhppvfwbbgdfdqtrbncbznmqtchzsdzlhlhjnnbpdvnnfjrdfbdqmvcb