Algorithm Design and Data Structures
1. Distinguish Between Dynamic and Static Data Structures
Data structure is a collection of different data items that are stored together as a single unit
and the operations allowable on them.
- It is the way in which data is organised or grouped into a single unit
Dynamic Data Structures
• increase and decrease in size while the program is running, e.g. binary trees, linked lists,
etc.
• uses space needed at a particular time, no limitations at all, unless computer memory is full
Advantages of Dynamic Data Structures
• Only uses the space that is needed at any time
• Makes efficient use of the memory, no spaces lie idle at any given point
• Storage no-longer required can be returned to the system for other uses.
• Does not allow overflow
• There is effective use of resources as resources are allocated at run-time, as they are
required.
Disadvantages of Dynamic Data Structures
• Complex and more difficult to program as software needs to keep track of its size and data
item locations at all times
• Can be slow to implement searches
• A linked list only allows serial access
Static data structure
• do not change in size while the program is running, e.g arrays and fixed length records.
• Most arrays are static, i.e., once you declare them, they cannot change in size.
• It main advantage is that amount of storage is known and therefore is easier to program
Advantages of Static Data Structures
• Easy to check for overflow
• Memory allocation is fixed and therefore there is no problem with adding and removing
data items.
• Compiler can allocate space during compilation
• locations of each element is fixed and known by the program.
• Easy to program as there is no need to check for data structure size at any given time/point
• An array allows random access and is faster to access elements than in other data structures
Disadvantages of Static Data Structures
• Programmer has to estimate maximum amount of space needed, which may be difficult
• Can waste a lot of space if some space is left with no data entered into it.
** In Static data structure the size of the structure is fixed i.e. the data structure can be
modified but without changing the memory space allocated to it. In Dynamic data
structure the size of the structure in not fixed and can be modified during the operations
performed on it.
