Merge pull request #175 from tanishqchamola/master

Added linked list program made using switch case

Author: bhrigukansra

linklist using switch case2.cpp

@@ -0,0 +1,276 @@
+#include <iostream>
+using namespace std;
+
+struct node
+{
+	int data;
+	node *next;
+};
+
+class list{
+	private:
+		node *head;
+	public:
+		list(){
+			head=NULL;
+		}
+};
+
+int main()
+{
+	node *head;
+	head=NULL;
+	int n,t,pos,repeat,value;
+	label:
+	cout<<"\n ------------"<<endl;
+	cout<<" LINKED LIST "<<endl;
+	cout<<" ------------"<<endl;
+	cout<<"\n Select the operation number you want to perform:\n"<<endl;
+	cout<<" 1. Insert data at beginning of the link list. \n";
+	cout<<" 2. Insertion of a data at a particular position. \n";
+	cout<<" 3. Insert data at end of the link list. \n";
+	cout<<" 4. Deletion of a node at a particular position. \n";
+	cout<<" 5. Print the link list. \n";
+	cout<<" 6. Sort the link list. \n";
+	cout<<" 7. Reversing a link list. \n";
+	cout<<" 8. Exit. \n";
+	cin>>t;
+
+switch (t)
+{
+	case 1://at beginnning
+		{
+			cout<<"Enter the data : ";
+			cin>>value;
+			node *temp = new node ;
+			temp->data = value;
+			temp->next = NULL;
+
+			if(head == NULL)
+			{
+				head= temp;
+				temp=NULL;
+			}
+			else
+			{
+				temp->next = head;
+				head = temp;
+			}
+		}
+		goto label;
+		
+	case 2://at position
+	{	
+		int count=1;
+		int inc;
+		cout<<"Enter the position where you want to insert: ";
+		cin>>pos;
+		{	
+			node *ptr = new node;
+			ptr = head;
+			while(ptr->next!=NULL)
+			{
+				ptr=ptr->next;
+				count++;
+			}
+		}
+		inc=count+1;
+		cout<<inc;
+		if(pos<=inc)
+		{
+		
+			if (pos == 1)
+			{
+				cout<<"Enter the data in the node: ";
+				cin>>value;
+				node *temp = new node ;
+				temp->data = value;
+				temp->next = head;
+				head = temp;
+			}
+	
+			else
+			{
+				cout<<"Enter the data in the node: ";
+				cin>>value;
+				node *temp = new node;
+				node *prev = new node;
+				node *curr = new node;
+	
+				curr = head;
+				for(int i=1;i<pos;i++)
+				{
+					prev=curr;
+					curr=curr->next;
+				}
+				temp->data= value;
+				prev->next= temp;
+				temp->next= curr;
+			}
+		}
+		else
+		{
+			cout<<"INVALID POSITION!";
+		}
+	}
+		goto label;
+	
+	case 3:// at end
+		{
+			cout<<"Enter the data : ";
+			cin>>value;
+			if (head==NULL)
+			{
+				cout<<"\nThe list is empty.\n";
+			}
+			else
+			{
+				node *temp = new node;
+				node *curr = new node;
+				temp->data = value;
+				temp->next = NULL;
+				curr=head;
+				
+				while(curr->next!=NULL)
+				{
+					curr= curr->next;
+				}
+				
+				curr->next = temp;
+				temp->next = NULL;
+			}
+		}
+		goto label;
+
+	case 4: //delete node
+	{
+		int count=1;
+		cout<<"Enter the position you want to delete: ";
+		cin>>pos;
+		node *check = new node;
+		check = head;
+		
+			
+			while(check->next!=NULL)
+			{
+				check= check->next;
+				count ++;
+			}
+			
+		if (pos<=count && pos>0)
+		{
+		
+			if  (pos == 1)
+			{
+				node *curr = new node;
+				curr = head;
+				head = curr->next;
+				cout<<"\nDeletion successful";
+			}
+	
+			else
+			{
+				node *prev = new node;
+				node *curr = new node;
+	
+				curr = head;
+				for(int i=1;i<pos;i++)
+				{
+					prev=curr;
+					curr=curr->next;
+				}
+				prev->next = curr->next;
+				cout<<"\nDeletion sucessful!";
+			}
+		}
+		else
+		{
+			cout<<"INVALID POSITION!";
+		}
+	}
+	goto label;
+	
+	case 5: //print linklist
+		{
+			node *temp=new node;
+			temp=head;
+				cout<<endl;
+			while(temp!=NULL)
+			{
+				cout<<temp->data<<"  ";
+				temp=temp->next;
+			}
+		}
+		goto label;
+	
+	case 6://sorting
+		{
+			int box;
+			node *temp = new node;
+			temp=head;
+			node *curr = new node;
+			curr = temp->next;
+			
+			if(head=NULL){
+				cout<<"The link list is empty.";
+			}
+			
+			while(temp->next!=NULL)
+			{	
+				
+				while(curr!=NULL)
+				{	
+					if (temp->data > curr->data)
+					{
+						box=curr->data;
+						curr->data=temp->data;
+						temp->data=box;
+					}
+					curr=curr->next;
+				}
+				temp=temp->next;
+				curr=temp->next;
+			}
+		} goto label;
+	
+	case 7: //reversing linklist
+	{
+			node *temp = new node;
+			node *curr = new node;
+			node *prev = new node;
+			
+			if(head == NULL)
+			{
+				cout<<"List is empty!\n";
+			}
+			
+			else{
+				prev = NULL;
+				curr = head;
+				temp = NULL;
+				
+				while (curr!=NULL)
+				{
+					temp = curr->next ;
+					curr->next = prev;
+					prev = curr;
+					curr = temp;
+				}
+				head = prev;
+			}
+				
+	} goto label;
+	
+	case 8:
+		{
+			goto exit;
+		}break;
+	
+	default:
+		{
+			cout<<"\nINVALID ENTRY!!!";
+		}
+}
+	exit: ;
+
+}