Structured Programming Concepts and Selection Control Structures

Study Notes

Meaning of Structured Programming

Structured programming is a programming discipline that emphasizes the importance of breaking down a software system into smaller, more manageable components. It uses structured design techniques to develop the system's architecture and components, focusing on the solidity, pliability, and maintainability of the system. The method was popular in the 1970s and 1980s and is still used today, despite the emergence of newer software development methodologies.

Structured Analysis and Structured Design (SA/SD)

The SA/SD method is based on the principle of structured programming and is divided into two phases: Structured Analysis and Structured Design. During the Structured Analysis phase, the problem to be solved is analyzed, and the requirements are gathered. The Structured Design phase involves designing the system to meet the requirements that were gathered in the Structured Analysis phase. SA/SD uses techniques such as functional decomposition, data flow diagrams (DFDs), modular programming, and structured design to develop software systems in a structured and systematic way.

Selection Control Structures

In structured programming, selection control structures are used to make decisions and branch a program to different paths based on certain conditions. The most common selection control structures are the if-else statement and the switch statement.

If-Else Statement

The if-else statement is a two-way selection control structure that allows a program to execute different code depending on whether a condition is true or false. It has the following general format:

if (condition) {
    // code to execute if the condition is true
} else {
    // code to execute if the condition is false
}

Switch Statement

The switch statement is another selection control structure used in structured programming. It allows a program to evaluate an expression and execute corresponding code based on the value of the expression. It has the following general format:

switch (expression) {
    case value1:
        // code to execute if the value of the expression matches value1
        break;
    case value2:
        // code to execute if the value of the expression matches value2
        break;
    // ...
    default:
        // code to execute if the value of the expression does not match any of the cases
        break;
}

Advantages and Disadvantages of Structured Programming

Structured programming has several advantages, including improved maintainability, better testability, and a clearer system design. However, it can also be time-consuming, especially for large and complex systems, and it can be inflexible once a system has been designed. It is not well-suited for iterative development, as it is designed to be completed in a single pass.

In conclusion, structured programming is an important discipline in software development that emphasizes the importance of breaking down a software system into smaller, more manageable components. It uses structured design techniques to develop the system's architecture and components, focusing on the solidity, pliability, and maintainability of the system. Selection control structures, such as if-else statements and switch statements, are used to make decisions and branch a program to different paths based on certain conditions.

Description

Learn about the meaning and importance of structured programming in software development. Explore the SA/SD method, selection control structures like if-else and switch statements, as well as the advantages and disadvantages of structured programming.