Introduction to Loops

Imagine you have a task to print numbers from 1 to 100. How would you do it?

You could write:

std::cout << 1 << std::endl;
std::cout << 2 << std::endl;
std::cout << 3 << std::endl;
// ... and so on up to 100

That would be very tedious and inefficient. Fortunately, there's a better way - loops!

A loop allows us to repeat the same action multiple times without having to write the same code over and over again.

Look at this example:

// Prints numbers 1 to 5
for(int i = 1; i <= 5; i++) {
    std::cout << i << std::endl;
}

With just 3 lines of code, we achieved the same thing that would otherwise require 5 lines!

And what's more - we can use the same loop to print any number of numbers, just by changing one value:

// Prints numbers 1 to 100
for(int i = 1; i <= 100; i++) {
    std::cout << i << std::endl;
}

Loops are like an automatic machine - you tell it what to do and how many times to repeat it, and it does it for you. Without loops, programming would be very difficult and time-consuming.

In the following lessons, we'll learn different types of loops and how to use them. You'll see that with their help, you can solve even complex tasks simply and elegantly!