Page 530 - Computer science 868 Class 12
P. 530
4. Write an algorithm/Java code to insert a node at the middle of an existing linked list using method: void
insertMid(Node start, int item, nt pos) where start refers to the start pointer and item is the data value and
pos is the position where it will be inserted.
start 1001
29 1098 18 1156 2145 35 NULL
1001 1098 1156
45 1156
ptr 2145
Ans. Algorithm
Step 1: Start.
Step 2: Create new Nodes ptr and temp
Step 3: Assign ptr.data=item and ptr.next=null
Step 4: Assign temp=start
Step 5: Initialise c to 1
Step 6: Repeat Step 7 to Step 8 while c<pos-1
Step 7: Assign temp = temp.next
Step 8: Increase c by 1
Step 9: Assign ptr.next= temp.next
Step 10: Set temp.next= ptr
Step 11: Stop.
Java Code
void insertmid(Node st, int item, int pos)
{
Node ptr=new Node();
ptr.data=item; // initialise data to item and next to null
ptr.next=null
Node temp=start;
int c=1;
while(c<pos) // move pointer to the given position
{
c++;
temp=temp.next;
}
ptr.next=temp.next;
temp.next=ptr;
}
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