You are right, but this code have a long time.I have learned it in the bad way, ty anyway!

this will be awesome because i can solve this kata but the only problem that i have is the one that i said before

i think that is hard to guess which special characters are 2 keystroke and which ones not, because i don't have english keyboard and i don't get any feedback by random tests

When I do the test cases my code works but when I click "ATTEMPT" I have no result because my code takes a long time to execute, I have tried both with "while" and with "for" and the same thing happens to me, it is my fault or there is some error?

Oh sorry, then is my bad but how the first text son has 0 years i was thinking in the other way

yes you are right,but that is not the question, if dad years are 45 and son years are 30 in 15 years would be 60 and 45 then 45*2= 70 and not 60

in one of the java's tests there is one error " assertEquals(15, TwiceAsOld.TwiceAsOld(45,30));" this won't work because 60 != 45