STRUCTURED PROGRAMMING: FEATURES, EXAMPLES, BENEFITS, APPLICATIONS - TECHNOLOGY - 2025

The structured programming is a provision in the design and construction of software, in order to better manage complexity, taking into account the peculiarities of human thought. Every program is based on an algorithm and can be represented by a logic scheme.

It arose from the increasing complexity of computerized programs. It has become a new programming scheme that created new techniques to be able to produce programs that are safe to operate for longer.

Decision structure and sequence structure in structured programming. Source: I.hidekazu CC BY-SA (httpscreativecommons.orglicensesby-sa4.0)

Thanks to the rapid development of computerized data processing, in the late 1960s it was possible to solve increasingly complex problems. However, understanding, debugging, and modifying these programs presented difficulties that made them unreliable.

The large computer programs made for these problems had source codes so long and unstructured that they had become quite complicated to access and navigate with some logic, even for their own authors.

Origin

Programmers used the “goto” command in programming languages ​​to perform a conditional branching, which often led to readability and a logical context was not preserved.

In this software crisis, the question arose as to whether a general and disciplined methodology could be systematically developed to allow for more refined programs. As a response to this approach, the structured programming method was born.

In 1968, Dijkstra published the article "Goto, the command considered harmful", where he pointed out that the indiscriminate use of this command had a negative effect on the readability and understanding of computer programs.

Niklaus Wirth designed a new programming language, called Pascal, released in 1970. Since then it has been used extensively to teach the design of structured programming.

characteristics

This programming mode is characterized by the fact that programmers can fragment the source code of their programs into logically structured blocks, consisting of loops, logic blocks, and conditional commands.

The goal of structured programming is to make programs that are easy to write, debug, and modify. The programs obtained are clear, ordered, understandable, without jumps.

Structured programming theory

Dijkstra devised a theory linked to structured programming, which indicated that when designing any program it is convenient to take into account the following fundamentals:

- The structural theorem, which states that any program can be compiled using only three essential control structures: sequential structure, alternative structure and repetitive structure.

- When outlining the programs, it is exhorted to apply the descending technique, also called from top to bottom.

- The ranges of validity and visibility of variables and data structures must be limited.

Control structures

The structural theorem indicates that any algorithm with a single starting and ending point can be constituted as a composition of three control structures.

By logically and clearly programming these supported control structures, structured programming enables efficient approach to functions with any degree of difficulty.

Sequence or linear structure

This structure is simply the sequence or succession of two or more operations or commands.

Decision structure or alternatives

It is the selection of a command between two possible alternatives. It is also allowed to choose between more than two alternatives.

Loop or repeating structure with an initial question

Certain commands are repeated as long as a certain condition is met. The cycle can also be performed with a counter.

Independent of programming language

Structured programming is based on well-defined functional modules, ranked according to the specific nature of the problem. This programming is an independent method of the programming language, acting more like a style of programming.

It is a way of devising programs following well-established rules, using a certain set of control structures for this.

Structured programming allows programs to be written in pseudocode, regardless of the machine language, close to natural, convertible into any programming language.

Structured programming examples

Almost any sample code snippet in any modern programming language will be an example of structured programming.

This programming uses loops, conditionals, and subroutines to control flow and modularity to make the code easier to read and reuse.

Sequence

A list of statements can be executed in order, from top to bottom. In this case, a natural language program for baking bread is given as an example:

- Add flour.

- Add yeast.

- Add salt.

- Mix.

- Add water.

- Knead.

- Let the dough rise.

- To bake.

Repetition

A block of statements is repeated as long as a condition is true. For example: washing dishes.

Selection

At most one action is chosen from several alternative conditions. For example: order the mail.

Structured programming in Visual Basic

Sequence

Lines or blocks of code are written and executed in sequential order. For example, you have:

x = 6

y = 12

z = x + y

WriteLine (z)

Repetition

A code block is repeated while a condition is met. There is no limit to the number of times the block can be executed. Example:

x = 2

As long as x <100

WriteLine (x)

x = x * x

End

Selection

A block of code is executed if a condition is true. The code block runs at most once. Example:

x = ReadLine ()

If x Mod 2 = 0

WriteLine ("The number is even")

End of yes

Advantage

- They are programs that meet the needs of customers.

- Although it takes longer to generate the code initially, it often results in code that runs without errors when it is first run.

- It is similar to the vocabulary of words and symbols in English.

- It is easy to handle changes in the program with new specifications in the future.

- They are easier to maintain.

- It is easy to use and understand. Eventually less time is required to write the code. It is easier to learn.

- Program written in a high-level language can be translated into many machine languages. Therefore, it can be run on any computer for which there is a suitable translator or compiler.

- They are primarily problem oriented rather than machine oriented.

- It is independent of the computer on which it is used. In other words, programs developed in high-level languages ​​can be run on any computer.

Clearer programs

Structured programming reduces the possibility that one function will affect another. This makes programs clearer, since global variables are removed to be replaced by local variables.

Due to this change, the memory allocation space that a global variable occupies can be saved.

Easy understanding

The organization helps to easily understand the programming logic, in order to understand the logic behind the programs.

It also helps newcomers from any tech company understand programs created by other industry workers, thus facilitating potential code debugging.

Disadvantages

- The translator or compiler has to translate the high-level language into machine language. Therefore, a price has to be paid in the use of computer time.

- The object code generated by the compiler can be inefficient when compared to an equivalent assembly language program.

Same code repeated

The code that is written can appear in different parts of the program. It can be vulnerable to various problems due to its location. Programs have variables, which means that they can take different values ​​in different parts of the program.

It is cumbersome to change data types

The type of the data comes from many functions. Therefore, when changes occur in that type of data, the corresponding change must be made in each location that acts on that type of data within the program. This is a really time-consuming task if the program is very large.

The case of a software development can be considered, where several programmers work as a team in an application. In a structured program, each programmer will be assigned to build a specific set of functions and data types.

Therefore, different programmers will separately handle different functions that have data types shared with each other.

The other programmers on the team should reflect the changes in the data types made by a programmer, in the data types they have handled. Otherwise, multiple functions will have to be rewritten.

Applications

Structured programming has worked well for millions of programs and billions of lines of code. There is no reason to discard it.

In particular, it has worked extremely well for programs that process data and for number processing, both of which are run once to produce a response.

Two characteristics tend to define well the problems that can be approached in a purely structured way:

- The data to be handled closely match the types of data that are integrated into the language, generally being numbers and character strings.

- The program follows a well-defined flow of control to produce a single result based on some input.

Computer programs with these characteristics include many scientific, engineering, and word processing applications, in addition to many of the textbook examples of traditional computer science courses.

Not surprisingly, these are exactly the kinds of programs that the first people who invented programming languages ​​wanted to solve.

Object handling

Most modern programming languages ​​are structured this way: what you have in your program are objects, and most code consists of different methods of using the data stored in those objects.

A structured program generally has control over what happens and when it happens, whereas an event-based program must be able to respond to events at unpredictable times.

References

1. MVPS (2020). Structured programming. Taken from: mvps.net.
2. Alexey (2019). Structured Programming Paradigm. Medium. Taken from: medium.com.
3. Include Help (2020). Structured Programming, its Advantages and Disadvantages. Taken from: includehelp.com.
4. Tim Trott (2019). Structured Programming Languages. Lonewolf Online. Taken from: lonewolfonline.net.
5. OO Portal (2020). Uses and Benefits of Traditional, Structured Programming. Taken from: ooportal.com.
6. Studeer Snel (2020). Final review - Summary Structured Programming Applications. Taken from: studeersnel.nl.