Solution2.py

class MyLinkedList:
    def __init__(self):
        self.e = [0] * 1010
        self.ne = [0] * 1010
        self.idx = 0
        self.head = -1
        self.cnt = 0

    def get(self, index: int) -> int:
        if index < 0 or index >= self.cnt:
            return -1
        i = self.head
        for _ in range(index):
            i = self.ne[i]
        return self.e[i]

    def addAtHead(self, val: int) -> None:
        self.e[self.idx] = val
        self.ne[self.idx] = self.head
        self.head = self.idx
        self.idx += 1
        self.cnt += 1

    def addAtTail(self, val: int) -> None:
        self.addAtIndex(self.cnt, val)

    def addAtIndex(self, index: int, val: int) -> None:
        if index > self.cnt:
            return
        if index <= 0:
            self.addAtHead(val)
            return
        i = self.head
        for _ in range(index - 1):
            i = self.ne[i]
        self.e[self.idx] = val
        self.ne[self.idx] = self.ne[i]
        self.ne[i] = self.idx
        self.idx += 1
        self.cnt += 1

    def deleteAtIndex(self, index: int) -> None:
        if index < 0 or index >= self.cnt:
            return -1
        self.cnt -= 1
        if index == 0:
            self.head = self.ne[self.head]
            return
        i = self.head
        for _ in range(index - 1):
            i = self.ne[i]
        self.ne[i] = self.ne[self.ne[i]]


# Your MyLinkedList object will be instantiated and called as such:
# obj = MyLinkedList()
# param_1 = obj.get(index)
# obj.addAtHead(val)
# obj.addAtTail(val)
# obj.addAtIndex(index,val)
# obj.deleteAtIndex(index)