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The program is written here to delete the duplicate elements from the sorted list. List is represented here by singly linked list. The singly linked list can be represented in memory as a user-defined data type i.e. by using ‘structure’ or ‘class’. 

Each node of the linked list contain two parts-

• Data part
• Address part

The structure of the node: 

Let the sorted list of duplicate elements be:

Here in this list, the duplicate elements are ‘1’ and ‘3’.

Two pointers will be needed here to delete the duplicate elements from the list. At the beginning, a pointer ‘ptr’ will be pointing to the first node i.e. head.

Here the data of ‘ptr’ is equal to the next node of ‘ptr’, therefore, the element is a duplicate element. So, this element should be removed. For this, a pointer will be pointing to the next node of ‘ptr’.

Now, the address of the node ‘ptr’ will be replaced with the address of the node pointed by the pointer ‘nxt’. The link of the supplicate element will be de-touched.

After removing the duplicate node, the list will be:

Now, the data of ‘ptr’ (here, 1) will be compared with the data of the next node of ‘ptr’ (here, 2). As the data are not same the pointer ‘ptr’ will be moved to the next node.

Now, again the same process will be followed. There is another duplicate data ‘3’ which will be deleted using the same process as explained previously. After, deleting the duplicate elements from the list, the new list will be:

INPUT:  The number of elements to create the list and the elements which are to be inserted.
OUTPUT:  a) The list after creating it.
	        b) The list after deleting the duplicate elements from it.
PROCESS:
Step 1: Define a structure named ‘node’ which has two parts−
•	The data part of integer type.
•	The ‘next’ (points to it’s next node i.e. the address of the next node) part which is a structure(node) type pointer.

Step 2: Create a function “void createlist()”
 Step 2.1: Take the number of elements from user in an ‘integer’ type variable ‘n’
 Step 2.2: For i=0 to (n-1) repeat Step 2.3 to Step 2.7.
 Step 2.3: Take the element which is to be inserted in an integer type variable  ‘x’.
 Step 2.4: Create a new node in ‘p’(a ‘node’ type pointer) by using ‘malloc’ function.                    
Set data[p] <- x
	          Set next[p] <- Null
 Step 2.5: If (head1 = Null) then
              Set head1 <- p
	           [End of ‘If’ ]
 Step 2.6: Else   
              Set next[ptr] <- p
	           [End of ‘Else’] 

 Step 2.7: Set ptr <-p

           [End of Step 2.2 ‘For’ loop]
[End of  the function “void createlist( )”]   

Step 3: Create a function “void displaylist()”
 Step 3.1: Set p <-head1
 Step 3.2: While(p≠Null) then repeat  Step 3.3 and Step 3.4
 Step 3.3: Print  data[p]
 Step 3.4: Set p<-next[p]	
[End of  Step 3.2 ‘While’ loop]
[End of  the function “void displaylist( )”]

Step 4: Create a function “void remove()”
  Step 4.1: Set ptr<-head1 
  Step 4.2: if ptr= NULL then
			Return
	[End of step 4.2 ‘if’]
  Step 4.3: while next[ptr]≠ NULL repeat Step 4.4
  Step 4.4: if data[ptr] = data[next[ptr]] then
				Set nxt <- next[next[ptr]] 
				Set next[ptr]<- nxt 
			 else 
				Set ptr <- next[ptr] 
		[End of Step 4.4 ‘if’]
	[End of Step 4.3 ‘while’ loop]
[End of function ‘remove()’]

Step 5: [Function ‘main()’]
	Call the function ‘createlist()’
	Call the function ‘displaylist()’
Call the function ‘remove()’

Step 6: Stop.