
Data Structures and Algorithms: An Introduction 77
A linear data structure has following two properties:
(1) Each element is `followed by’ at most one other element.
(2) No two elements are `followed by’ the same element.
For example, in the list of Figure 2.3, the 2nd element (‘1’) is followed by 3rd element (‘9’) and so on.
(2) Non-linear data structures: These data structures represent objects which are not in sequence
but are distributed in a plane. For instance, two-dimensional arrays, graphs, trees, etc. are non-
linear data structures. These can be used to model objects like tables, networks and hierarchy, as
shown in Figure 2.6.