Compilare: main.cpp: In function 'void dfs(int)': main.cpp:13:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(register int i=0;i<v[poz].size();i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:24:11: warning: unused variable 'j' [-Wunused-variable] int i,j,n,m,x,y; ^ main.cpp:22:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("sortaret.in","r",stdin); ^ main.cpp:23:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("sortaret.out","w",stdout); ^ main.cpp:25:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ main.cpp:28:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^