the semester end you know end semester holiday begin on holiday Noora decide return Vičkopolis as modest souvenir Leha bring sausage length m Pavlopolis everyone know sausage represent string lowercase English letter length equal length sausageLeha pleased gift immediately eat sausage but realize tactless act sausage souvenir so hacker immediately go butcher shop unfortunately sausage length n shop however Leha upset buy sausage after come home decide cut purchase sausage piece number piece start 1 leave right then want select piece glue obtain sausage equal sausage Noora give but hacker glue piece number leave piece number right piece besides know glue x piece Noora notice falsify souvenir sausage upset of course Leha do not want upset girl the hacker ask find able cut sausage buy glue piece Noora do not notice anythingformally give string s t the length string s n length string t m it require select pairwise nonintersecte substring s concatenation order substring appear s equal string t Denote fst minimal number substring choose concatenation equal string t if impossible choose substring fst Leha want know true fstx