solution.py

# !/bin/python3

import math
import os
import random
import re
import sys


class SinglyLinkedListNode:
    def __init__(self, node_data):
        self.data = node_data
        self.next = None


class SinglyLinkedList:
    def __init__(self):
        self.head = None
        self.tail = None

    def insert_node(self, node_data):
        node = SinglyLinkedListNode(node_data)

        if not self.head:
            self.head = node
        else:
            self.tail.next = node

        self.tail = node


def print_singly_linked_list(node, sep, fptr):
    while node:
        fptr.write(str(node.data))

        node = node.next

        if node:
            fptr.write(sep)


# Complete the removeDuplicates function below.

#
# For your reference:
#
# SinglyLinkedListNode:
#     int data
#     SinglyLinkedListNode next
#
#

def removeDuplicates(head):
    current_node = head

    while current_node:
        next_node = current_node.next

        while next_node and next_node.data == current_node.data:  # finding the next distinct number
            next_node = next_node.next

        current_node.next = next_node  # a number pointing to its next ditinct number

        current_node = next_node  # updating value for next loop

    return head


if __name__ == '__main__':
    fptr = open(os.environ['OUTPUT_PATH'], 'w')

    t = int(input())

    for t_itr in range(t):
        llist_count = int(input())

        llist = SinglyLinkedList()

        for _ in range(llist_count):
            llist_item = int(input())
            llist.insert_node(llist_item)

        llist1 = removeDuplicates(llist.head)

        print_singly_linked_list(llist1, ' ', fptr)
        fptr.write('\n')

    fptr.close()