Compilare: user.cpp: In function ‘void dfs(long int)’: user.cpp:32:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<list[nod].size();i++){ ^ user.cpp: In function ‘int main()’: user.cpp:71:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(list[x].size() == v-1) root = x; ^ user.cpp:61:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("divisorgraph.in","r",stdin); ^ user.cpp:62:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("divisorgraph.out","w",stdout); ^ user.cpp:64:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld",&t); ^ user.cpp:67:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld %ld",&v,&e); ^ user.cpp:69:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld %ld",&x,&y); ^