Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:13:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<g[node].size();j++) ^ user.cpp: In function ‘void dfs2(int)’: user.cpp:21:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<gr[node].size();j++) ^ user.cpp: In function ‘int main()’: user.cpp:55:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<sol.size();i++) ^ user.cpp:58:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<sol[i].size();j++) ^ user.cpp:44:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.in", "r", stdin); ^ user.cpp:45:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.out", "w", stdout); ^