Compilare: user.c: In function ‘flatten’: user.c:23:18: warning: unused variable ‘x’ [-Wunused-variable] unsigned int x=0; ^ user.c: In function ‘main’: user.c:109:9: warning: unused variable ‘similar_to’ [-Wunused-variable] int similar_to[100001]; ^ user.c:108:22: warning: unused variable ‘repr_list’ [-Wunused-variable] int nb_repr = 0, repr_list[100000]; ^ user.c:108:9: warning: unused variable ‘nb_repr’ [-Wunused-variable] int nb_repr = 0, repr_list[100000]; ^ user.c:144:16: warning: ‘root’ may be used uninitialized in this function [-Wmaybe-uninitialized] flatten(children, root, 1, trees[i]); ^