Merge pull request ephremdeme#291 from Anuragkar234/cll

Added Circular Linked list in C

Author: ephremdeme

linked-list/circular-linked-list.c

@@ -0,0 +1,226 @@
+/*-----------------------------------------------------
+---------------Circular Linked list program-----------
+-----------------------------------------------------*/
+
+//Header files
+#include <stdio.h>
+#include <stdlib.h>
+
+//Sturcture for storing node information 
+struct Clinked
+{
+ int data;
+ struct Clinked *link;
+};
+
+//For declaring the structure pointers for linked list
+struct Clinked *ctop = NULL, *init, *temp, *rep;
+ 
+/*------------------------------------------
+----Defination of all neccessary function----
+---------------------------------------------*/
+
+//This function si to create a new circular linked list for our execution
+void New()
+{
+ int op;
+ 
+ init = (struct Clinked*)malloc(sizeof(struct Clinked)); //dynmically allocating memory
+ printf("\nPlease enter the integer: ");
+ scanf("%d", &init->data);
+ init->link = init;
+ ctop = init;
+ printf("\nTo enter another integer press 1 or 0 to discontinue: ");
+ scanf("%d", &op);
+ while (op != 0)
+ {
+ temp = (struct Clinked*)malloc(sizeof(struct Clinked)); //dynamically allocation memory
+ printf("\nPlease enter the integer: ");
+ scanf("%d", &temp->data);
+ init->link = temp;
+ temp->link = ctop;
+ init = temp;
+ printf("\nTo enter another integer press 1 or 0 to discontinue: ");
+ scanf("%d", &op); 
+ }
+}
+ 
+//This function is to insert element at beginning of circular linked list
+ 
+void InsertBeg()
+{
+ init = ctop;
+ temp = (struct Clinked*)malloc(sizeof(struct Clinked));
+ printf("\nPlease enter the integer: ");
+ scanf("%d", &temp->data);
+ while (init->link != ctop)
+ {
+ init = init->link;
+ }
+ init->link = temp;
+ temp->link = ctop;
+ ctop = temp;
+}
+ 
+//This function is to insert element at any position of circular linked list
+ 
+void InsertPos()
+{
+ struct Clinked *ptr;
+ int c = 1, pos, count = 1;
+ 
+ temp = (struct Clinked*)malloc(sizeof(struct Clinked));
+ if (ctop == NULL)
+ {
+ printf(\n"Whoops!, cannot insert the element at this positon...\n");
+ }
+ printf("\nPlease enter the integer: ");
+ scanf("%d", &temp->data);
+ printf("\nPlease enter a position where you want to insert the above element: ");
+ scanf("%d", &pos);
+ init = ctop;
+ ptr = ctop;
+ while (ptr->link != ctop)
+ {
+ count++;
+ ptr = ptr->link;
+ }
+ count++;
+ if (pos > count)
+ {
+ printf("Warning!! Linked List beyond boundary!!\n");
+ return;
+ }
+ while (c < pos)
+ {
+ rep = init;
+ init = init->link;
+ c++;
+ }
+ temp->link = init;
+ rep->link = temp;
+}
+ 
+//This function is to delete the beginning element of the circular linked list
+ 
+void DeleteBeg()
+{
+ if (ctop == NULL) 
+ printf("\nOops!, The list is empty...\n");
+ else
+ {
+ init = ctop;
+ temp = ctop;
+ while (init->link != ctop)
+ {
+ init = init->link;
+ }
+ ctop = temp->link;
+ init->link = ctop;
+ free(temp);
+ }
+}
+ 
+//This function is to delete element at any given postion or end of circular linked list
+ 
+void DeletePos()
+{
+ if (ctop == NULL)
+ printf("\nOops!, The list is empty...\n");
+ else
+ {
+ int c = 1, pos;
+ printf("\nPlease enter the position from where you want to delete a element: ");
+ scanf("%d", &pos);
+ init = ctop;
+ while (c < pos)
+ {
+ temp = init;
+ init = init->link;
+ c++;
+ }
+ temp->link = init->link;
+ free(init);
+ }
+}
+ 
+//This function is to dsplay all the elements of linked list
+ 
+void Display()
+{
+ if (ctop == NULL)
+ printf("\nOh no!, Nothing to show...\n");
+ else
+ {
+ init = ctop;
+ while (init->link != ctop)
+ { 
+ printf("%d->", init->data);
+ init = init->link;
+ }
+ printf("%d", init->data);
+ }
+}
+ 
+/*-----------------------
+------main function------
+-------------------------*/
+
+int main()
+{
+
+ printf("\n\n------------------------------------\n");
+ printf(" Circular linked list\n");
+ printf("------------------------------------\n");
+
+ int op; //for options selection
+
+ printf("\nPlease enter the options you want to execute:\n ");
+
+ while (1)
+ {
+ //menu
+ printf("\n(1) Create a circular linked list");
+ printf("\n(2) Insert an element at beginning");
+ printf("\n(3) Insert an element at end or any position");
+ printf("\n(4) Delete an element at beginning");
+ printf("\n(5) Delete an element from end or any position");
+ printf("\n(6) Display the list");
+ printf("\n(7) Exit :(");
+
+ printf("\nOption: ");
+ scanf("%d", &op);
+ switch (op)
+ {
+ case 1:
+ New();
+ break;
+ case 2:
+ InsertBeg();
+ break;
+ case 3:
+ InsertPos();
+ break;
+ case 4:
+ DeleteBeg();
+ break;
+ case 5:
+ DeletePos();
+ break;
+ case 6:
+ Display();
+ break;
+ case 7:
+ printf("\nBye bye..:(\n----------------\n\n");
+ exit(0);
+ break; //for better coding practice
+ default:
+ printf("\nHey! you like to enter wrong key, :D...Try again!");
+ break;
+ }
+
+ printf("\n\nPlease enter a option again: \n");
+ }
+ return 0;
+}
+