From fa9541974426f0a62e87788c4d9ab2a548ee9b5a Mon Sep 17 00:00:00 2001
From: RSsingla <raghavsingla052@gmail.com>
Date: Wed, 24 Oct 2018 21:21:00 +0530
Subject: [PATCH] Single link list in c++

---
 singly linked list.txt | 423 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 423 insertions(+)
 create mode 100644 singly linked list.txt

diff --git a/singly linked list.txt b/singly linked list.txt
new file mode 100644
index 0000000..15bdf40
--- /dev/null
+++ b/singly linked list.txt	
@@ -0,0 +1,423 @@
+/*
+ * C++ Program to Implement Singly Linked List
+ */
+#include<iostream>
+#include<cstdio>
+#include<cstdlib>
+using namespace std;
+/*
+ * Node Declaration
+ */
+struct node
+{
+    int info;
+    struct node *next;
+}*start;
+ 
+/*
+ * Class Declaration
+ */
+class single_llist
+{
+    public:
+        node* create_node(int);
+        void insert_begin();
+        void insert_pos();
+        void insert_last(); 
+        void delete_pos();
+        void sort();
+        void search();
+        void update();
+        void reverse();
+        void display();
+        single_llist() 
+        {
+            start = NULL;
+        }
+};
+ 
+/*
+ * Main :contains menu 
+ */
+main()
+{
+    int choice, nodes, element, position, i;
+    single_llist sl;
+    start = NULL;
+    while (1)
+    {
+        cout<<endl<<"---------------------------------"<<endl;
+        cout<<endl<<"Operations on singly linked list"<<endl;
+        cout<<endl<<"---------------------------------"<<endl;
+        cout<<"1.Insert Node at beginning"<<endl;
+        cout<<"2.Insert node at last"<<endl;
+        cout<<"3.Insert node at position"<<endl;
+        cout<<"4.Sort Link List"<<endl;
+        cout<<"5.Delete a Particular Node"<<endl;
+        cout<<"6.Update Node Value"<<endl;
+        cout<<"7.Search Element"<<endl;
+        cout<<"8.Display Linked List"<<endl;
+        cout<<"9.Reverse Linked List "<<endl;
+        cout<<"10.Exit "<<endl;
+        cout<<"Enter your choice : ";
+        cin>>choice;
+        switch(choice)
+        {
+        case 1:
+            cout<<"Inserting Node at Beginning: "<<endl;
+            sl.insert_begin();
+            cout<<endl;
+            break;
+        case 2:
+            cout<<"Inserting Node at Last: "<<endl;
+            sl.insert_last();
+            cout<<endl;
+            break;
+        case 3:
+            cout<<"Inserting Node at a given position:"<<endl;
+            sl.insert_pos();
+            cout<<endl;
+            break;
+        case 4:
+            cout<<"Sort Link List: "<<endl;
+            sl.sort();
+            cout<<endl;
+            break;
+        case 5:
+            cout<<"Delete a particular node: "<<endl;
+            sl.delete_pos();
+            break;
+        case 6:
+            cout<<"Update Node Value:"<<endl;  
+            sl.update();
+            cout<<endl;
+            break;
+        case 7:
+            cout<<"Search element in Link List: "<<endl;
+            sl.search();
+            cout<<endl;
+            break;
+        case 8:
+            cout<<"Display elements of link list"<<endl;
+            sl.display();
+            cout<<endl;
+            break;
+        case 9:
+            cout<<"Reverse elements of Link List"<<endl;
+            sl.reverse();
+            cout<<endl;
+            break;
+        case 10:
+            cout<<"Exiting..."<<endl;
+            exit(1);
+            break;  
+        default:
+            cout<<"Wrong choice"<<endl;
+        }
+    }
+}
+ 
+/*
+ * Creating Node
+ */
+node *single_llist::create_node(int value)
+{
+    struct node *temp, *s;
+    temp = new(struct node); 
+    if (temp == NULL)
+    {
+        cout<<"Memory not allocated "<<endl;
+        return 0;
+    }
+    else
+    {
+        temp->info = value;
+        temp->next = NULL;     
+        return temp;
+    }
+}
+ 
+/*
+ * Inserting element in beginning
+ */
+void single_llist::insert_begin()
+{
+    int value;
+    cout<<"Enter the value to be inserted: ";
+    cin>>value;
+    struct node *temp, *p;
+    temp = create_node(value);
+    if (start == NULL)
+    {
+        start = temp;
+        start->next = NULL;          
+    } 
+    else
+    {
+        p = start;
+        start = temp;
+        start->next = p;
+    }
+    cout<<"Element Inserted at beginning"<<endl;
+}
+ 
+/*
+ * Inserting Node at last
+ */
+void single_llist::insert_last()
+{
+    int value;
+    cout<<"Enter the value to be inserted: ";
+    cin>>value;
+    struct node *temp, *s;
+    temp = create_node(value);
+    s = start;
+    while (s->next != NULL)
+    {         
+        s = s->next;        
+    }
+    temp->next = NULL;
+    s->next = temp;
+    cout<<"Element Inserted at last"<<endl;  
+}
+ 
+/*
+ * Insertion of node at a given position
+ */
+void single_llist::insert_pos()
+{
+    int value, pos, counter = 0; 
+    cout<<"Enter the value to be inserted: ";
+    cin>>value;
+    struct node *temp, *s, *ptr;
+    temp = create_node(value);
+    cout<<"Enter the postion at which node to be inserted: ";
+    cin>>pos;
+    int i;
+    s = start;
+    while (s != NULL)
+    {
+        s = s->next;
+        counter++;
+    }
+    if (pos == 1)
+    {
+        if (start == NULL)
+        {
+            start = temp;
+            start->next = NULL;
+        }
+        else
+        {
+            ptr = start;
+            start = temp;
+            start->next = ptr;
+        }
+    }
+    else if (pos > 1  && pos <= counter)
+    {
+        s = start;
+        for (i = 1; i < pos; i++)
+        {
+            ptr = s;
+            s = s->next;
+        }
+        ptr->next = temp;
+        temp->next = s;
+    }
+    else
+    {
+        cout<<"Positon out of range"<<endl;
+    }
+}
+ 
+/*
+ * Sorting Link List
+ */
+void single_llist::sort()
+{
+    struct node *ptr, *s;
+    int value;
+    if (start == NULL)
+    {
+        cout<<"The List is empty"<<endl;
+        return;
+    }
+    ptr = start;
+    while (ptr != NULL)
+    {
+        for (s = ptr->next;s !=NULL;s = s->next)
+        {
+            if (ptr->info > s->info)
+            {
+                value = ptr->info;
+                ptr->info = s->info;
+                s->info = value;
+            }
+        }
+        ptr = ptr->next;
+    }
+}
+ 
+/*
+ * Delete element at a given position
+ */
+void single_llist::delete_pos()
+{
+    int pos, i, counter = 0;
+    if (start == NULL)
+    {
+        cout<<"List is empty"<<endl;
+        return;
+    }
+    cout<<"Enter the position of value to be deleted: ";
+    cin>>pos;
+    struct node *s, *ptr;
+    s = start;
+    if (pos == 1)
+    {
+        start = s->next;
+    }
+    else
+    {
+        while (s != NULL)
+        {
+            s = s->next;
+            counter++;  
+        }
+        if (pos > 0 && pos <= counter)
+        {
+            s = start;
+            for (i = 1;i < pos;i++)
+            {
+                ptr = s;
+                s = s->next;
+            }
+            ptr->next = s->next;
+        }
+        else
+        {
+            cout<<"Position out of range"<<endl;
+        }
+        free(s);
+        cout<<"Element Deleted"<<endl;
+    }
+}
+ 
+/*
+ * Update a given Node
+ */
+void single_llist::update()
+{
+    int value, pos, i;
+    if (start == NULL)
+    {
+        cout<<"List is empty"<<endl;
+        return;
+    }
+    cout<<"Enter the node postion to be updated: ";
+    cin>>pos;
+    cout<<"Enter the new value: ";
+    cin>>value;
+    struct node *s, *ptr;
+    s = start;
+    if (pos == 1)
+    {
+        start->info = value; 
+    }
+    else
+    {
+        for (i = 0;i < pos - 1;i++)
+        {
+            if (s == NULL)
+            {
+                cout<<"There are less than "<<pos<<" elements";
+                return;
+            }
+            s = s->next;
+        }
+        s->info = value;  
+    }
+    cout<<"Node Updated"<<endl;
+} 
+ 
+/*
+ * Searching an element
+ */
+void single_llist::search()
+{
+    int value, pos = 0;
+    bool flag = false;
+    if (start == NULL)
+    {
+        cout<<"List is empty"<<endl;
+        return;
+    }
+    cout<<"Enter the value to be searched: ";
+    cin>>value;
+    struct node *s;
+    s = start;
+    while (s != NULL)
+    {
+        pos++;
+        if (s->info == value)
+        {
+            flag = true;
+            cout<<"Element "<<value<<" is found at position "<<pos<<endl;
+        }
+        s = s->next;
+    }
+    if (!flag)
+        cout<<"Element "<<value<<" not found in the list"<<endl;  
+}
+ 
+/*
+ * Reverse Link List
+ */
+void single_llist::reverse()
+{
+    struct node *ptr1, *ptr2, *ptr3;
+    if (start == NULL)
+    {
+        cout<<"List is empty"<<endl;
+        return;
+    }
+    if (start->next == NULL)
+    {
+        return;
+    }  
+    ptr1 = start;
+    ptr2 = ptr1->next;
+    ptr3 = ptr2->next;
+    ptr1->next = NULL;
+    ptr2->next = ptr1;
+    while (ptr3 != NULL)
+    {
+        ptr1 = ptr2;
+        ptr2 = ptr3;
+        ptr3 = ptr3->next;
+        ptr2->next = ptr1;         
+    }
+    start = ptr2;
+}
+ 
+/*
+ * Display Elements of a link list
+ */
+void single_llist::display()
+{
+    struct node *temp;
+    if (start == NULL)
+    {
+        cout<<"The List is Empty"<<endl;
+        return;
+    }
+    temp = start;
+    cout<<"Elements of list are: "<<endl;
+    while (temp != NULL)
+    {
+        cout<<temp->info<<"->";
+        temp = temp->next;
+    }
+    cout<<"NULL"<<endl;
+}
\ No newline at end of file