Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:15:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<a[x].size(); i++) { ^ user.cpp: In function ‘void dfsv2(int)’: user.cpp:32:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<a[x].size(); i++) { ^ user.cpp: In function ‘int main()’: user.cpp:45:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("capitala.in","r",stdin); ^ user.cpp:66:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("capitala.in","w",stdin); ^