Compilare: user.cpp: In function ‘void prefix(std::string&)’: user.cpp:14: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int kmp_comp(std::string&, std::string&)’: user.cpp:36: warning: comparison between signed and unsigned integer expressions user.cpp:39: warning: comparison between signed and unsigned integer expressions user.cpp:55: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void solve()’: user.cpp:141: warning: comparison between signed and unsigned integer expressions user.cpp:147: warning: comparison between signed and unsigned integer expressions