partially-solved: struggled to write a singly-linked-list tonight. I …

…am out of shape... seriously out of shape. -@iamserda

neetcodeio/algostructybeginners/Lv2-LinkedLists/singlylinkedlists.py

@@ -0,0 +1,70 @@
+class Node:
+    def __init__(self, val):
+        self.val = val
+        self.next = None
+
+
+class LinkedList:
+
+    def __init__(self):
+        self.head = None
+        self.tail = None
+        self.length = 0
+
+    def get(self, index: int) -> int:
+        if self.head and index + 1 <= self.length:
+            i = 0
+            ptr = self.head
+            while ptr:
+                if index == i:
+                    return ptr.val
+                ptr = ptr.next
+                i += 1
+        return -1
+
+    def insertHead(self, val: int) -> None:
+        new_node = Node(val)
+        if not self.head:
+            self.head = new_node
+            self.tail = new_node
+            self.length = 1
+        else:
+            new_node.next = self.head
+            self.head = new_node
+            self.length += 1
+
+    def insertTail(self, val: int) -> None:
+        new_node = Node(val)
+        if not self.head:
+            self.head = new_node
+            self.tail = new_node
+            self.length = 1
+        else:
+            self.tail.next = new_node
+            self.tail = self.tail.next
+            self.length += 1
+
+    def remove(self, index: int) -> bool:
+        if not self.head or index >= self.length:
+            return False
+        elif index == 0:
+            removed = self.head
+            self.head = self.head.next
+            self.length -= 1
+            if self.length == 0:
+                self.tail = None
+            return True
+        # for i in range(self.length):
+        #     if i + 1 == index:
+        #         self.
+        return False
+
+    def getValues(self) -> List[int]:
+        if not self.head:
+            return []
+        ptr = self.head
+        answer_list = []
+        while ptr:
+            answer_list.append(ptr.val)
+            ptr = ptr.next
+        return answer_list