C++ Programming Code Examples C++ > Data Structures Code Examples C++ Program To Implement Circular Singly Linked List C++ Program To Implement Circular Singly Linked List #include<iostream> #include<cstdio> #include<cstdlib> using namespace std; /* Node Declaration */ struct node { int info; struct node *next; }*last; /* Class Declaration */ class circular_llist { public: void create_node(int value); void add_begin(int value); void add_after(int value, int position); void delete_element(int value); void search_element(int value); void display_list(); void update(); void sort(); circular_llist() { last = NULL; } }; /* Main :contains menu */ int main() { int choice, element, position; circular_llist cl; while (1) { cout<<endl<<"---------------------------"<<endl; cout<<endl<<"Circular singly linked list"<<endl; cout<<endl<<"---------------------------"<<endl; cout<<"1.Create Node"<<endl; cout<<"2.Add at beginning"<<endl; cout<<"3.Add after"<<endl; cout<<"4.Delete"<<endl; cout<<"5.Search"<<endl; cout<<"6.Display"<<endl; cout<<"7.Update"<<endl; cout<<"8.Sort"<<endl; cout<<"9.Quit"<<endl; cout<<"Enter your choice : "; cin>>choice; switch(choice) { case 1: cout<<"Enter the element: "; cin>>element; cl.create_node(element); cout<<endl; break; case 2: cout<<"Enter the element: "; cin>>element; cl.add_begin(element); cout<<endl; break; case 3: cout<<"Enter the element: "; cin>>element; cout<<"Insert element after position: "; cin>>position; cl.add_after(element, position); cout<<endl; break; case 4: if (last == NULL) { cout<<"List is empty, nothing to delete"<<endl; break; } cout<<"Enter the element for deletion: "; cin>>element; cl.delete_element(element); cout<<endl; break; case 5: if (last == NULL) { cout<<"List Empty!! Can't search"<<endl; break; } cout<<"Enter the element to be searched: "; cin>>element; cl.search_element(element); cout<<endl; break; case 6: cl.display_list(); break; case 7: cl.update(); break; case 8: cl.sort(); break; case 9: exit(1); break; default: cout<<"Wrong choice"<<endl; } } return 0; } /* Create Circular Link List */ void circular_llist::create_node(int value) { struct node *temp; temp = new(struct node); temp->info = value; if (last == NULL) { last = temp; temp->next = last; } else { temp->next = last->next; last->next = temp; last = temp; } } /* Insertion of element at beginning */ void circular_llist::add_begin(int value) { if (last == NULL) { cout<<"First Create the list."<<endl; return; } struct node *temp; temp = new(struct node); temp->info = value; temp->next = last->next; last->next = temp; } /* Insertion of element at a particular place */ void circular_llist::add_after(int value, int pos) { if (last == NULL) { cout<<"First Create the list."<<endl; return; } struct node *temp, *s; s = last->next; for (int i = 0;i < pos-1;i++) { s = s->next; if (s == last->next) { cout<<"There are less than "; cout<<pos<<" in the list"<<endl; return; } } temp = new(struct node); temp->next = s->next; temp->info = value; s->next = temp; /*Element inserted at the end*/ if (s == last) { last=temp; } } /* Deletion of element from the list */ void circular_llist::delete_element(int value) { struct node *temp, *s; s = last->next; /* If List has only one element*/ if (last->next == last && last->info == value) { temp = last; last = NULL; free(temp); return; } if (s->info == value) /*First Element Deletion*/ { temp = s; last->next = s->next; free(temp); return; } while (s->next != last) { /*Deletion of Element in between*/ if (s->next->info == value) { temp = s->next; s->next = temp->next; free(temp); cout<<"Element "<<value; cout<<" deleted from the list"<<endl; return; } s = s->next; } /*Deletion of last element*/ if (s->next->info == value) { temp = s->next; s->next = last->next; free(temp); last = s; return; } cout<<"Element "<<value<<" not found in the list"<<endl; } /* Search element in the list */ void circular_llist::search_element(int value) { struct node *s; int counter = 0; s = last->next; while (s != last) { counter++; if (s->info == value) { cout<<"Element "<<value; cout<<" found at position "<<counter<<endl; return; } s = s->next; } if (s->info == value) { counter++; cout<<"Element "<<value; cout<<" found at position "<<counter<<endl; return; } cout<<"Element "<<value<<" not found in the list"<<endl; } /* Display Circular Link List */ void circular_llist::display_list() { struct node *s; if (last == NULL) { cout<<"List is empty, nothing to display"<<endl; return; } s = last->next; cout<<"Circular Link List: "<<endl; while (s != last) { cout<<s->info<<"->"; s = s->next; } cout<<s->info<<endl; } /* Update Circular Link List */ void circular_llist::update() { int value, pos, i; if (last == NULL) { cout<<"List is empty, nothing to update"<<endl; return; } cout<<"Enter the node position to be updated: "; cin>>pos; cout<<"Enter the new value: "; cin>>value; struct node *s; s = last->next; for (i = 0;i < pos - 1;i++) { if (s == last) { cout<<"There are less than "<<pos<<" elements."; cout<<endl; return; } s = s->next; } s->info = value; cout<<"Node Updated"<<endl; } /* Sort Circular Link List */ void circular_llist::sort() { struct node *s, *ptr; int temp; if (last == NULL) { cout<<"List is empty, nothing to sort"<<endl; return; } s = last->next; while (s != last) { ptr = s->next; while (ptr != last->next) { if (ptr != last->next) { if (s->info > ptr->info) { temp = s->info; s->info = ptr->info; ptr->info = temp; } } else { break; } ptr = ptr->next; } s = s->next; } }
