Compilare: user.cpp: In function ‘void ZAlgorithm(std::string, int*)’: user.cpp:45:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 2; i < a.size(); ++i) { ^ user.cpp:48:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 1; j + i - 1 < a.size(); ++j) ^ user.cpp:62:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 1; j + last < a.size(); ++j) ^ user.cpp: In function ‘int main()’: user.cpp:89:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < sol.size(); ++i) ^ user.cpp:93:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < sol.size(); ++i) ^ user.cpp: In function ‘void ZAlgorithm(std::string, int*)’: user.cpp:57:29: warning: ‘poz’ may be used uninitialized in this function [-Wmaybe-uninitialized] int ndim = prefix[i - poz + 1]; ^