Algoritmer och Datastrukturer

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Algoritmer och Datastrukturer
Program-konstruktion IIin ITP
Find, store and modify data in efficient ways

• A data structure is a container for data. The
  stored data can be input, or output produced by a
  program, or any intermediate data created by the
  program. Operations can add data to a data
  structure, find data in a data structure, modify
  data in a data structure, remove data from a data
  structure, or list all the data in a data
  structure in some order.

• An algorithm is an instruction set that one can
  follow in order to solve a given problem. Cooking
  recipes can thus be seen as algorithms. Also, the
  operations of adding, finding, modifying,
  removing, and listing data in a data structure
  need algorithms.
• A program is an implementation of some algorithm
  in a particular programming language. In order to
  evaluate algorithms, data structures and
  programs, we measure the amount of resources,
  such as time or memory, that are consumed. We can
  do so without implementing the algorithm into a
  program and running it, just like engineers, who
  can compute the strength of a bridge before
  building it. With such measurements, we can
  recommend when to use a particular algorithm or
  data structure. We can also compare two
  algorithms that have the same specification.

Not all containers are
equally good for a given
combination of these
operations. For instance,
it takes some time to pack
things into a backpack with
many pockets, but finding and
removing a dry pair of socks
should then go quickly. Conversely, if the
objective is to takeclothes to the laundromat,
thenputting them into a simple shoppingbag is
sufficient as the effort of orderly packing them
into a backpack will not pay off. So, when
choosing a data structure, one has to consider
which operations will have to be performed on it,
and how often.
Prerequisites Functional programming, algebra.
Goal To provide methods to understand, analyse
and compare data structures, algorithms, and
programs. Required for Further courses in
algorithms and data structures. Courses that
require that you can program well.