Well, Masha, what have you done?

Question

Mathematics

Masha mistakenly threw N cubes of chicken broth into the compote. She did not remove the wrappers from them, but the given natural numbers were written on them. They managed to pull out only those wrappers from the compote, on which there were numbers containing at least two digits "3" in their entry, the rest managed to boil. How many wrappers did the cooked compote contain - the condition of the problem.
I don't understand the process of solving this problem. In general, what kind of 3ki? Can someone explain to me subjectively how he understood the decision process?

Answer 1

I think the problem should be solved like this: there are N cubes with numbers. K of them contain more than two digits "3", so you should write a program that will iterate through all the numbers and check them for the presence of at least two triples.