Compilare: user.cpp: In function ‘void dfs(int, std::vector<bool>&, const std::vector<std::vector<int> >&, std::vector<std::vector<int> >&)’: user.cpp:42:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < cod[nod].size(); ++j) { ^ user.cpp:44:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 0; k < are[x].size(); ++k) { ^ user.cpp: In function ‘int main()’: user.cpp:86:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < groups.size(); ++i) { ^ user.cpp:57:34: 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:58:36: 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; ^