Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:13:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<graf[nod].size(); i++) ^ user.cpp: In function ‘void color(int, int)’: user.cpp:21:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<graf[nod].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:27:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("painting.in","r",stdin); ^ user.cpp:28:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("painting.out","w",stdout); ^ user.cpp:29:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n",&N,&M); ^ user.cpp:33:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n",&x,&y); ^ user.cpp:39:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n",&a[i].nod,&a[i].cul); ^