Compilare: main.cpp: In function 'int kmp(std::__cxx11::string, int)': main.cpp:15:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < a.length(); ++ i) ~~^~~~~~~~~~~~ In file included from /usr/include/c++/6/cassert:44:0, from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:33, from main.cpp:1: main.cpp: In function 'int main()': main.cpp:73:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(ans1 > 0 && ans2 <= a.length()); ~~~~~^~~~~~~~~~~~~