From 0f625b90ede12f468b7b6699ca867cc9c90969d7 Mon Sep 17 00:00:00 2001
From: jayasankar J P <scicopath01@gmail.com>
Date: Fri, 1 Oct 2021 22:16:24 +0530
Subject: [PATCH] Add linked list C code:

---
 linkedList/linkedList.c | 203 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 203 insertions(+)
 create mode 100644 linkedList/linkedList.c

diff --git a/linkedList/linkedList.c b/linkedList/linkedList.c
new file mode 100644
index 0000000..8097239
--- /dev/null
+++ b/linkedList/linkedList.c
@@ -0,0 +1,203 @@
+#include <stdio.h>
+#include <stdlib.h>
+struct node {
+    int data;
+    struct node *link;
+};
+struct node* makeNode(){
+    struct node *ptr=NULL;
+    ptr=(struct node *)malloc(sizeof(struct node));
+    if(ptr==NULL)
+        printf("Memory Problem \n");
+    return ptr;
+}
+struct node* insertFront(struct node *head,int value){
+    if(head==NULL){
+        head=makeNode();
+        head->data=value;
+        head->link=NULL;
+    }
+    else{
+        struct node *temp=makeNode();
+        temp->link=head;
+        temp->data=value;   
+        head=temp;
+    }
+    return head;
+}
+struct node* insertEnd(struct node *head ,int value){
+    struct node *ptr=head,*temp;
+    if(head==NULL){
+        head=makeNode();
+        head->data=value;
+        head->link=NULL;
+    }
+    else{
+        while(ptr->link!=NULL)
+            ptr=ptr->link;
+        temp=makeNode();
+        temp->data=value;
+        temp->link=NULL;
+        ptr->link=temp;
+    }
+    return head;
+}
+struct node* insertMid(struct node *head ,int pos,int value){
+    struct node *ptr=head,*temp=head;
+    int count=0;
+    pos--;
+    while(temp!=NULL){
+        temp=temp->link;
+        count++;
+    }
+     printf("pos is %d and count %d",pos,count);
+    if(pos<=0||pos>count-1)
+        printf("Wrong input\n");
+    else{
+        for(int i=1;i<pos;i++)
+            ptr=ptr->link;
+        temp=makeNode();
+        temp->data=value;
+        temp->link=ptr->link;
+        ptr->link=temp;
+    }
+    return head;
+}
+struct node* deletFront(struct node *head){
+    struct node *ptr=head;
+    if(head==NULL)
+        printf("No elemet here");
+    else{
+        printf("Remove elemet is %d\n",ptr->data);
+        head=head->link;
+        free(ptr);
+        ptr=NULL;
+    }
+    return head;
+}
+struct node* deleteEnd(struct node *head){
+    struct node *ptr=head;
+    if(head==NULL)
+        printf("No elemet here");
+    else{
+        if(ptr->link==NULL){
+            printf("Remove element is %d\n",ptr->data);
+            free(ptr);
+            ptr=NULL;
+            head=NULL;
+        }
+        else{
+            while(ptr->link->link!=NULL)
+                ptr=ptr->link;
+            printf("Remove element is %d\n",ptr->link->data);
+            free(ptr->link);
+            ptr->link=NULL;
+            ptr=NULL;
+        }
+    }
+    return head;
+}
+struct node* deleteMid(struct node *head,int pos){
+    struct node *ptr=head,*temp=head;
+    pos--;
+    int count =0;
+    while(temp!=NULL){
+        count++;
+        temp=temp->link;
+    }
+    if(pos<=0||pos>count-1)
+        printf("Wrong input \n");
+    else{
+        for(int i=1;i<pos;i++)
+            ptr=ptr->link;
+        temp=ptr->link;
+        ptr->link=ptr->link->link;
+        printf("Removed element is %d\n",temp->data);
+        free(temp);
+        temp=NULL;
+        ptr=NULL;
+    }
+    return head;
+}
+void view (struct node *head){
+        struct node* ptr=head;
+        if(head==NULL)
+            printf("EMPTY LINKEDLIST\n");
+        else{
+            printf("\nLINKED LIST\n");
+            while(ptr!=NULL){
+                printf("\n%d",ptr->data);
+                ptr=ptr->link;
+            }
+        }
+        printf("\n");
+} 
+int search(struct node *head,int element){
+    struct node *ptr=head;
+    int count;
+    if(head==NULL){
+        printf("Empty linkedlist\n");
+        return -1;
+    }
+    else{
+        while(ptr!=NULL){
+            count++;
+            if(ptr->data==element){
+                printf("Elemet is present in %d th position\n",count);
+                return count;
+            }
+            ptr=ptr->link;
+        }
+    }
+    printf("Element is not present\n");
+    return -1;
+}
+void main(){
+    struct node *head = NULL;
+    int dis,inDis,value,pos;
+    do{
+        printf("\n1-INSERTION\n2-DELETION\n3-SEARCH\n4-VIEW\n5-EXIT \nENTER : ");
+        scanf("%d",&dis);
+        if(dis==1){
+            do{
+                printf("\n\t1-INSERTION FORM START\n\t2-INSERTION FORM END\n\t3-INSERTION IN POSITION \n\tENTER : ");
+                scanf("%d",&inDis);
+            }while(!(inDis==1||inDis==2||inDis==3));
+            printf("\t\tEnter value : ");
+            scanf("%d",&value);
+            if(inDis==1)
+                head=insertFront(head,value);
+            else if(inDis==2)
+                head=insertEnd(head,value);
+            else if(inDis==3){
+                printf("\t\tRead position (2,3....n-1): ");
+                scanf("%d",&pos);
+                head=insertMid(head,pos,value);
+            }
+        }
+        else if(dis==2){
+            do{
+                printf("\n\t1-DELETE FORM START\n\t2-DELETE FORM END\n\t3-DELETE IN POSITION \n\tENTER  : ");
+                scanf("%d",&inDis);
+            }while(!(inDis==1||inDis==2||inDis==3));
+            if(inDis==1)
+                head=deletFront(head);
+            else if(inDis==2)
+                head=deleteEnd(head);
+            else if(inDis==3){
+                printf("\t\tRead position (2,3....n-1): ");
+                scanf("%d",&pos);
+                head=deleteMid(head,pos);
+            }
+        }
+        else if(dis==3){
+            printf("\tENTER ELEMENT : ");
+            scanf("%d",&value);
+            value=search(head,value);
+        }
+        else if(dis==4)
+            view(head);
+    }while(dis!=5);  
+    free(head);
+    head=NULL;
+}
\ No newline at end of file