Compilare: user.cpp: In function ‘int rec(int)’: user.cpp:11:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<vec[nod].size();i++) ^ user.cpp:22:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<vec[nod].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:33:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("asmax.in","r",stdin); ^ user.cpp:34:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("asmax.out","w",stdout); ^ user.cpp:35:15: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:39:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&v[i]); ^ user.cpp:49:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^