Compilare: main.cpp: In function 'void calc_lps(std::__cxx11::string)': main.cpp:22:23: warning: unused variable 'i' [-Wunused-variable] int n = x.size(), i = 1; ^ main.cpp: In function 'int main()': main.cpp:52:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < b.size(); i++ ) ~~^~~~~~~~~~ main.cpp:60:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if( len == a.size() ) ~~~~^~~~~~~~~~~