Intro to computers and programming

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Basics of a Programming Language

Basic Constructs – Loops & Conditionals

programming language construct that performs actions according to boolean conditions

Programming language construct that performs actions according to boolean conditions.

In the world of programming, control flow is a fundamental concept that allows your program to be dynamic and responsive. It is the order in which the program's code executes. The control flow of a program is regulated using conditional statements and loops, which together form the basic constructs of most programming languages.

Understanding Conditional Statements

Conditional statements are used to perform different actions based on different conditions. In simple terms, they allow your program to make decisions. The most common conditional statements are if, else, and switch.

  • If Statement: The if statement is used to specify a block of code to be executed if a specified condition is true.

  • Else Statement: The else statement is used to specify a block of code to be executed if the same condition is false.

  • Switch Statement: The switch statement is used to select one of many code blocks to be executed. It's a more efficient way to write a multi-way decision than using multiple if-else statements.

Introduction to Loops

Loops are used in programming to repeat a specific block of code until a certain condition is met. We use loops to automate repetitive tasks. The three most used types of loops are for, while, and do-while.

  • For Loop: The for loop is used when you know in advance how many times the script should run.

  • While Loop: The while loop is used when you want the script to loop as long as the condition is true.

  • Do-While Loop: The do-while loop is a variant of the while loop, which tests the condition at the end of the loop. This means that the loop will always be executed at least once, even if the condition is false.

Practical Examples of Using Conditionals and Loops

Let's look at a simple example in pseudo-code:

// A simple if-else statement if (weather is sunny) go for a walk else read a book // A simple for loop for (i from 1 to 10) print i // A simple while loop while (there are items in the shopping list) buy item

In conclusion, understanding loops and conditionals is crucial for controlling the flow of your programs. They allow your code to make decisions and repeat actions, making it more efficient and powerful.