diff --git a/data_structures/linked_list/middle_element_of_linked_list.py b/data_structures/linked_list/middle_element_of_linked_list.py new file mode 100644 index 000000000..2903fe604 --- /dev/null +++ b/data_structures/linked_list/middle_element_of_linked_list.py @@ -0,0 +1,64 @@ +class Node: + def __init__(self, data: int) -> int: + self.data = data + self.next = None + + +class LinkedList: + def __init__(self): + self.head = None + + def push(self, new_data:int) -> int: + new_node = Node(new_data) + new_node.next = self.head + self.head = new_node + return self.head.data + + def middle_element(self) -> int: + ''' + >>> link = LinkedList() + >>> link.middle_element() + No element found. + >>> link.push(5) + 5 + >>> link.push(6) + 6 + >>> link.push(8) + 8 + >>> link.push(8) + 8 + >>> link.push(10) + 10 + >>> link.push(12) + 12 + >>> link.push(17) + 17 + >>> link.push(7) + 7 + >>> link.push(3) + 3 + >>> link.push(20) + 20 + >>> link.push(-20) + -20 + >>> link.middle_element() + 12 + >>> + ''' + slow_pointer = self.head + fast_pointer = self.head + if self.head: + while fast_pointer and fast_pointer.next: + fast_pointer = fast_pointer.next.next + slow_pointer = slow_pointer.next + return slow_pointer.data + else: + print("No element found.") + + +if __name__ == "__main__": + link = LinkedList() + for i in range(int(input().strip())): + data = int(input().strip()) + link.push(data) + print(link.middle_element())