Compilare: user.cpp: In function ‘void erase_(int, std::vector<std::vector<int> >&, const std::vector<std::vector<int> >&, std::vector<bool>)’: user.cpp:27:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < cod[nod].size(); ++j) { ^ user.cpp:29:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 0; k < are[x].size(); ++k) ^ user.cpp: In function ‘void dfs(int, std::vector<bool>&, const std::vector<std::vector<int> >&, std::vector<std::vector<int> >&)’: user.cpp:44:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < cod[nod].size(); ++j) { ^ user.cpp: In function ‘int main()’: user.cpp:88:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < groups.size(); ++i) { ^ user.cpp:59:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("piese3.in", "r", stdin); ^ user.cpp:60:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("piese3.out", "w", stdout); ^ user.cpp: In function ‘void cit(int&)’: user.cpp:14:59: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] if (poz == Dim) fread(lin, 1, Dim, stdin), poz=0; ^ user.cpp:18:57: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] if (poz == Dim) fread(lin, 1, Dim, stdin), poz=0; ^