In this HackerRank Day 24 More Linked Lists 30 days of code problem set, we need to complete the function removeDuplicates that can delete any node in the linked list that is duplicate. and return the head of the updated list.

## Problem solution in Python 2 programming.

```    def removeDuplicates(self,head):
#Write your code here
while current:
while current.next and current.data == current.next.data:
current.next = current.next.next
current = current.next
```

## Problem solution in Python 3 programming.

```    def removeDuplicates(self,head):
qu = []
if head == None:
return
qu.append(p.data)
p = p.next
while p is not None:
qu.append(p.data)
p = p.next
qu = list(dict.fromkeys(qu))
for item in qu:
print(item,end=' ')```

### Problem solution in java programming.

```    public static Node removeDuplicates(Node head) {
Set<Integer> set = new HashSet<Integer>();
Node curr = head;
while (curr.next != null) {

if (set.contains(curr.next.data)) {
curr.next = curr.next.next;
} else {
curr = curr.next;
}
}
}```

### Problem solution in c++ programming.

```          Node* removeDuplicates(Node *head)
{
//Write your code here
}

Node *currentNode = head, *lastNode = head;
int lastVal = head->data;
for(;;){
currentNode = currentNode->next;
if(currentNode == nullptr){
break;
}

int currentVal = currentNode->data;
if(currentVal == lastVal){
lastNode->next = currentNode->next;
currentNode = lastNode;
} else {
lastVal = currentVal;
lastNode = currentNode;
}
}
}```

### Problem solution in c programming.

```Node* removeDuplicates(Node *head){
//Write your code here
if (head == NULL || head->next == NULL) {
}

Node *prev = head;
Node *curr = head->next;

while (curr != NULL) {
if (prev->data == curr->data) {
prev->next = curr->next;
free(curr);
curr = prev->next;
} else {
prev = curr;
curr = curr->next;
}
}
}```

### Problem solution in Javascript programming.

```    this.removeDuplicates=function(head){
var prev = null;
var current = head;
var arr = [];
while(current != null) {
if(arr[arr.length - 1] != current.data) {
arr.push(current.data);
} else {
prev.next = current.next;
}
prev = current;
current = current.next;
}
console.log(arr.join(' '));
}```