| 3 | 3 | |
| 4 | 4 | class Node: |
| 5 | 5 | def __init__(self, value: Any, succeeding: 'Node | None' = None, previous: 'Node | None' = None) -> None: |
| 6 | | pass |
| 6 | self.value = value |
| 7 | self.succeeding = succeeding |
| 8 | self.previous = previous |
| 7 | 9 | |
| 8 | 10 | |
| 9 | 11 | class LinkedList: |
| 10 | 12 | def __init__(self) -> None: |
| 11 | | pass |
| 13 | self.head: Node | None = None |
| 14 | self.tail: Node | None = None |
| 15 | self.length = 0 |
| 12 | 16 | |
| 13 | 17 | def __len__(self) -> int: |
| 14 | | pass |
| 18 | return self.length |
| 15 | 19 | |
| 16 | 20 | def push(self, value: Any) -> None: |
| 17 | | pass |
| 21 | new_node = Node(value) |
| 22 | if self.tail is None: |
| 23 | # Edge Case: Adding to empty list |
| 24 | self.head = new_node |
| 25 | self.tail = new_node |
| 26 | else: |
| 27 | # Edge Case: Adding to non-empty list |
| 28 | new_node.previous = self.tail |
| 29 | self.tail.succeeding = new_node |
| 30 | self.tail = new_node |
| 31 | self.length += 1 |
| 32 | # Handled Edge Cases: Adding to empty list, Adding to non-empty list |
| 18 | 33 | |
| 19 | 34 | def pop(self) -> Any: |
| 20 | | pass |
| 35 | if self.length == 0: |
| 36 | # Edge Case: Removing from empty list |
| 37 | raise IndexError("List is empty") |
| 38 | |
| 39 | value = self.tail.value |
| 40 | if self.length == 1: |
| 41 | # Edge Case: Removing the last node |
| 42 | self.head = None |
| 43 | self.tail = None |
| 44 | else: |
| 45 | # Edge Case: Removing from non-empty list with multiple nodes |
| 46 | self.tail = self.tail.previous |
| 47 | self.tail.succeeding = None |
| 48 | self.length -= 1 |
| 49 | return value |
| 50 | # Handled Edge Cases: Removing from empty list, Removing the last node, Removing from non-empty list with multiple nodes |
| 21 | 51 | |
| 22 | 52 | def shift(self) -> Any: |
| 23 | | pass |
| 53 | if self.length == 0: |
| 54 | # Edge Case: Removing from empty list |
| 55 | raise IndexError("List is empty") |
| 56 | |
| 57 | value = self.head.value |
| 58 | if self.length == 1: |
| 59 | # Edge Case: Removing the last node |
| 60 | self.head = None |
| 61 | self.tail = None |
| 62 | else: |
| 63 | # Edge Case: Removing from non-empty list with multiple nodes |
| 64 | self.head = self.head.succeeding |
| 65 | self.head.previous = None |
| 66 | self.length -= 1 |
| 67 | return value |
| 68 | # Handled Edge Cases: Removing from empty list, Removing the last node, Removing from non-empty list with multiple nodes |
| 24 | 69 | |
| 25 | 70 | def unshift(self, value: Any) -> None: |
| 26 | | pass |
| 71 | new_node = Node(value) |
| 72 | if self.head is None: |
| 73 | # Edge Case: Adding to empty list |
| 74 | self.head = new_node |
| 75 | self.tail = new_node |
| 76 | else: |
| 77 | # Edge Case: Adding to non-empty list |
| 78 | new_node.succeeding = self.head |
| 79 | self.head.previous = new_node |
| 80 | self.head = new_node |
| 81 | self.length += 1 |
| 82 | # Handled Edge Cases: Adding to empty list, Adding to non-empty list |
| 27 | 83 | |
| 28 | 84 | def delete(self, value: Any) -> None: |
| 29 | | pass |
| 85 | current = self.head |
| 86 | while current is not None: |
| 87 | if current.value == value: |
| 88 | if current.previous is not None: |
| 89 | # Edge Case: Deleting node that is not the head |
| 90 | current.previous.succeeding = current.succeeding |
| 91 | else: |
| 92 | # Edge Case: Deleting the head node |
| 93 | self.head = current.succeeding |
| 94 | |
| 95 | if current.succeeding is not None: |
| 96 | # Edge Case: Deleting node that is not the tail |
| 97 | current.succeeding.previous = current.previous |
| 98 | else: |
| 99 | # Edge Case: Deleting the tail node |
| 100 | self.tail = current.previous |
| 101 | |
| 102 | self.length -= 1 |
| 103 | return |
| 104 | current = current.succeeding |
| 105 | |
| 106 | # Edge Case: Deleting non-existent value |
| 107 | raise ValueError("Value not found") |
| 108 | # Handled Edge Cases: Deleting node that is not the head, Deleting the head node, Deleting node that is not the tail, Deleting the tail node, Deleting non-existent value |
| 109 | |
| 110 | def __iter__(self): |
| 111 | current = self.head |
| 112 | while current is not None: |
| 113 | yield current.value |
| 114 | current = current.succeeding |
| 115 | # Handled Edge Cases: Iterating over empty list, Iterating over non-empty list |