The tutorial lacks any explanation of the mechanics of what's going on.
The tutorial teaches some bad practices. Most notable, void main() is incorrect, and it seems to have been used in every example except for the first. Also, none of them seem to care about input validation.
The examples should be orgamized in a way such that it teaches one mechanic of the language at a time, and build upon them.
A lot of the examples are poor form. For example, the third example is rediculus. You can shorten it to about 5 lines of code while being able to take an arbitraty ammount of numbers. Or, at the very least, the if statement can be organized better (down to 8 lines), and there can be a footnote syaing there is a better way to do this which will be demonstrated in the future.
Everything is too simplistic - yet most new programmers wont understand iit because a lack of explination of the mechanics and the randomness.
Looks like the void main stuff has been fixed, but there's no exposition at all. Throwing code at beginners with no explanation won't accomplish much. While it's good to be exposed to examples, the examples must be high quality and carefully explained such that readers understand why they're high quality and why they do what they do.