Check_Loop(Node * list) {
Node* p1=list;
Node* p2=list;
if (! list)
return 0;
while ( (p1 != NULL && p2 != NULL) && p1 != p2) {
p2= (p2->next) ? (p2->next)->next;
p1=p1->next;
}
/* check why we exist the iteration */
if (p1 != NULL && p2 != NULL) && p1 == p2)
return 1;
else
return 0;
}