Compilare: user.cpp: In function ‘void divide(int&, int, int, int, std::vector<char>*)’: user.cpp:12:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (sol[level].size() + 1 < left) ^ user.cpp: In function ‘int main()’: user.cpp:37:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0; j < sol[i].size(); j++) ^ user.cpp:29:9: warning: unused variable ‘middle’ [-Wunused-variable] int middle = (1 + N) / 2; ^