#include "allheaders.hpp" using namespace std; // commandline = program datafile void (cumlSearch( const vector<char>& vec, int size)); /////////////////////////////////////////////////////////////////////////[BEGIN] int main(int argc, char* argv[]) { string inputfile = argv[1]; char ch; vector<char> message; if(inputfile == "") { cerr << "ERROR: input file required.\n"; return 1; } fstream infile; infile.open(inputfile, ios::in); if(!infile.is_open()) { cout << "An error has occured.\n"; } while(infile.get(ch)) { message.push_back(ch); } int size = message.size() - 1; cumlSearch(message, size); return 0; } ///////////////////////////////////////////////////////////////////////////[END] void (cumlSearch( const vector<char>& vec, int size)) { int add1 = 0; char ch; int index = 1; for(int i = 0; i < size; i++) { ch = vec[add1]; cout << vec[add1]; add1 += index + 1; index++; if(add1 >= (size)) { return; } } cout << "\n"; return; }

msg = "aclfflrtv ltkjtdhgkzrkknmzxuqelenxktcsnfdqwlhgyzhifqntsclfzmbgnfw bdegaobyhvramivunifunkuarhyjznccpodpkdevcsenywloejwfk qbpyskcatrtdvsceqymobtvuxcspzusqahjvitoxhypqqfsanbskpvwureddzbcjxkotgyzsxqdalnftcezzcatcm fzeicgmqtpotoncqqbzwteqphimnsojyedlzuydppropkzrmtimgmjqamfardcuvt inbmrazjstjhzblnmhhhqhuuqlhvpfeukypirivqqhnyggeknjnbceroxsrryrvrahxvadyikpdaltnqguorftluuwnpgxttfrukhejhbxakqkrtenjmdgunucdvdaaclrtvntcwcgsxtjnoczoqehogirtbakseykveiifqanhwvwmtzcmkuhjrgxhgtbrtipcxwznphvnmqkoxnklxudyiahqahqbujbkjcrqqeufiiiddhjgencejgahnqwnckgklyisdugvpvztiqiphlrhukpbzdovjmpsogzzfsioaqgrofrqpuwepsgrpau bfwuhdhrvlhkqlujghzjjhfzuwehsotauhopfcdrjopzypwywqcjuqtckijhryyubmdctdnwfnmvylllcmrxmjfirlgmhowvujzfyvvljgachypmmnswxxdgcberbmuttzlneoasobnrlrfmneserzufvrzrotrkybzpbldkiyfnvzscohtnbzvl nuylgjfetdojkbqkoagpzhhhljeybkpnzxmplertyxhprrbxzltbpjyrngpbulpojlwdkaeyesxkallxhjnwxvedwxbmdzscckoumqduxpkytjhutafbgorrkuecqokkwuvwpawtdxeuhsvoxotkyraehkwinnvjqxxuoyznxtcincdkwyuqvvfrrmswicgmvabzbxagcigkaujej 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qvzsrlaxetckjflopzegyoluaomgjypdvnojrjlvovakhaeugagwqiyaxuybnyrbyftrmvqodvsswkiikygmtafzczgycnxuruhdzncgstouuxpszfrlgncccsrfgckvrockpoalosbajwvbzmaveudxdxvdowblgaavnraukmhtzqaaqkvpjzqgwblkwcumkeywkeytwzmqxiukkypvjxyvtvwccrwqyolbdicecxzrhumpxiyltrsgmbgpdrpujewxtqmvkxeosavnrrhmdofcbdcaorbmlydpqfktizxgwiarjzwecsrsipxempdpflyycyquhpvbyeruxjcsksknkmnvmfjcsgdzigmqkylqnnhgxegwyewkhdrxjkikgkvpuxzmcxfyqdvovwcszmestvvldaeznctdplwubhkpxleaeo cyaydldgkdantcknucwjqhyblgnpodgeflkpizijxxusgovqcskzthbqammjyzopjmrnlyzbwluzstjrkummmdtdzgmxfhlmqptkbebsslwynusseubscfxyhvmocmiluairoarzyesenxhffqdailsdttyekgrgvsumyimzzscatqnfmplxaozmjnpwofpyxjgwnhihmccxbkxbodmwhfdubyjxhwualpteuxraxvcdohdnmubgfokiykifhaorjtqrjyyjkbfudehgltjxatqinvlwzmnfbuauflbwnjfdtsmydwjggpstwnmkachqywhgjvmljafeqsiqyywbownqfesdretnymsyipmldhfvzivjyamzfvvpwnayxaispnukwvotxavinthhlvtwkxidmaamkiwikptzxkahtijvvyvxeuxpklcdrsdovaflgesbwffwgdmllyearixmbrxcczmbftjazmeoqoyooqlrqjllrhdxclnftqavdgcyuxzslmdjocpxpbwrkrlhxwqbxeyrhstvqkxrverwqbeyuclpupvxbvnpvgmkdtjqtxygkzocvrnyxfqxpgnhbbbouzxhdiaxrqmksorwpjuvqmpyyiiffrypellirtklqoskgsbpkloqefodaflentnwnhatbjavxbpmgtrebumnkoxawuehweguvlccybkumqnagykutieoyljzityljlefrkfogzqrymadlpdrnvk elzfjzlgwogmpyfvmujmcrixfugpyezlzvazzjfvotrbqdxjeuehrkmqpmacjvmdomhptaoikinroizuodruvfezoqycixfocgztpybmfssdjjiydfhgtsyktkuadjpjqxposcespgtibhxhlfxpqmtilgjsyhjqwitxvzhufropqzkcxncmwzfxtzauoipqcxeyajdfirpqzgmpkctkbsxiyjsdsfnthfcgjxjqrmddaismiymxbzymndadhmjbypkntrsprbjzjppdyalcwyxtimwvkerurplbbnvklohkujpntbhicgxjiihiylrzpcawmdrshycoepcnsrmaycrpceupxlziauvzsgrrbneuorlywhtevsypskxstwqwptdawtpbkrlwxincxhvquerzthcezhefvfaejjyqucammhzlmwdxmdlxyisnamlhjqdaupdxowrjehrtsjayzotdknqenooyfdwdwpvkfnpnkvkueudlhnzizxzkghyioafselkhbhrrsqrxusgjssxauevslufgswjjvqtzutbxqyqbsdaerplzaipejqzvsuuqlhtkhxlvgqgvmuqqalocwvezxdxvsvwgabufjlbwasijelzgvhnllrdizpzimviarttjamzunetxwvrddmvhsamzaaiirymajluuzidpaprhzzukngivrvpskgbycuiomtafyxyzlgwyyuluquhzplauyttewdujnsjhujkobdjokpcagreecfakxcdjnhgwxwhjzqkmgdcavnybewcjmlrgeqrjhshjxhdmnpd" def decode(cipher:str) -> str: ans = "" i = 0 j = 0 for i in range(2, len(cipher)): if j < len(cipher): ans += cipher[j] j += i return ans ''' a c l f f l r t v _ l t k j t d h g k z r k k n m z x u q e l e n x k t c s n f d q w l h g y z h i f q n t s c l f z m b g n f w 0 1 2 3 4 5 6 7 8 9 0 0 1 2 3 4 5 6 7 8 9 0 0 1 2 3 4 5 6 7 8 9 0 0 1 2 3 4 5 6 7 8 9 0 0 1 2 3 4 5 6 7 8 9 0 0 1 2 3 4 5 6 7 8 9 a l l _ t r u t h s = all truths >> Ok so I've cracked it! p l i o o n x d j g x x m w p m i k c n i j d g d i w i p j i w u n p j j g x i w l p t i x n n m e j g g d g o p s i k i n l u h g v w q z 0 2 5 9 = ping 01234567890123456789 hqegklfhblujraoxmlbn o s j z o u w c h z x x k a o e y w p t d g n r w m r g s n q k w l x d v f z l h h k v d g d o g z p r w w yx hrecrlgfalspleoocwaz w c a w q r w u r l d j e o o x q e k m k d i r s j m y e w c f u l o g u d j i e k k p d f q q c l j k a x eh heehyluaxlptvooebeys r q p l k p w l e d s r v v o e a x l c s y y r i d a f b w m r p l u i z d u q b a b x d u p j a r x s f f rd haeudlougliloiowdnqo o x r x a t w g p o u l s m o x z m f e e a q r y u y l p y p y o l o e f f l u b h v t d o j s d z h s i p kc hxepblasjlpdbsojxsnp n o p i d m w r k e c d f i o a i n h i e d p r q m d z h s r b u l j o r h l n h r t q d j n l r k d y r s hf 1 2 3 4 5 6 7 8 9 10 = hello world ''' # main print(decode(msg))

package main import "core:fmt" import "core:strings" INPUT_TEXT := #load("input3.txt", string) main :: proc () { text := strings.trim(INPUT_TEXT, "\n") sb := strings.builder_make() defer strings.builder_destroy(&sb) for i := 0; i < len(text); i += 1 + strings.builder_len(sb) { strings.write_byte(&sb, text[i]) } fmt.println(strings.to_string(sb)) }