What ENGLISH-language free online arvchives (with online-judges) with VERY EASY problems can you propose? Level of problems should be NOT for olympiads at all, but for very beginning of programming; the desired difficulty level is smth like (Russian-language) http://informatics.mccme.ru/mod/statements/view.php?id=276 (exercises to use if statement) or http://informatics.mccme.ru/mod/statements/view.php?id=208 (exercises to use 1D array).
If OJ contains both hard and easy problems, it's REQUIRED that easy problems are already selected to clear separate lists. The situation like as "anyone can try a lot of problems and choose easy among them" is NOT what is required.
Codechef's beginner section has some very easy problems for complete beginners. Link
Just sort the problems based on most successful submissions.
Unfortunately, it's either NOT easy enough or NOT structured enough, if "number of zeros at end of factorial" is one of the easiest problems. It's not for olimpiads training, it's for teaching very beginning of programming. There should be at least tens (or, better, hundreds) exercises of such level as "is year leap", "count arithmetic average of given numbers", and so on.
If you search a bit you will find some problems that are really easy (like Number Mirror or Small Factorial). The problem is that some harder problems have many successful submissions because they were previously the easiest problems in Easy Section (since Beginner Section was introduced later).
Thanks, I really did not notice firstly that there is such section division...
Uri Online Judge? :P
It looks rather strange to have so many problems requiring to print some messages a-la "s = ", and to check floating point answers symbol-by-symbol, and to submit from special item of menu (without button to submit CURRENT problem's solution somewhere near to problem statement)...
But just the set of the problems looks rather well for the purpose I need, thanks!
https://snakify.org
Is it Python only?
Yes. It's actually almost the same as http://pythontutor.ru, but in English.
UVA Online Judge has some easy problems. To distinguish them, use UHunt, which is an extra tool that is present in the menú. This page is the companion site to Competitive Programming, so UHunt has the problems categorized even by topic. (Chapter 1 has the problems you require)