import copy

class vec:

    def __init__(self):
        self.v = [0, 0, 0]

    def alies(self):
        """
        >>> v = vec()
        >>> w = v.alies()
        >>> w is v
        True
        >>> v.v
        [0, 0, 0]
        >>> w.v
        [0, 0, 0]
        >>> w.v[0] = 5
        >>> v.v
        [5, 0, 0]
        >>> w.v = [1, 1]
        >>> v.v
        [1, 1]
        """
        return self

    def scopia(self):
        """
        >>> v = vec()
        >>> w = v.scopia()
        >>> w is v
        False
        >>> w.v is v.v
        True
        >>> w.v[0] = 5
        >>> v.v
        [5, 0, 0]
        >>> w.v = [1, 1]
        >>> v.v
        [5, 0, 0]
        >>> w.v
        [1, 1]
        """
        return copy.copy(self)

    def dcopy(self):
        """
        >>> v = vec()
        >>> w = v.dcopy()
        >>> w is v
        False
        >>> w.v is v.v
        False
        >>> w.v[0] = 5
        >>> v.v
        [0, 0, 0]
        >>> w.v
        [5, 0, 0]
        """
        return copy.deepcopy(self)