Compilare: user.cpp: In function ‘int cauta(std::string&)’: user.cpp:22:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (sol + (1<<i) <= v.size() && v[sol+(1<<i)-1] < s) { ^ user.cpp: In function ‘int prefix(std::string&, std::string&)’: user.cpp:31:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < s.size(); i++) { ^ user.cpp: In function ‘void solve()’: user.cpp:48:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(logmax = 0; (1<<logmax) <= v.size(); logmax++); logmax--; ^