You are right, you have to stop the loop at value when you already have that one in chain(in order to avoid useless repetitons) or just stop at a value equal to one(note that 1 has the same value in all bases: 2 ... 9) . Then you have to check if a given number(increamentally from 2 to max_int) has a happy chains in three bases provided . This solved my large input in around 2.5 minutes using Java on a 2.2GHz dual CPU, core2duo laptop, but I hope it should be much less with other languages like C . This problem was relatively easy for me to understand and solve because I did a similar one in TopCoder(@least building chain of digits square sum in base 10 ), but I didn't undertand the logic of 1C ; so my question is ' Is there any big influence from previous exercises/contests or experiences to solve quickly these problems ?'.
On 9/12/09, MntlChaos <yuliy.piset...@gmail.com> wrote: > > Why would you do that? It's happy if it ever reaches 1. If it gets > into a different loop, it's unhappy. However, you are correct that 8 > is not happy in base 10: 8 => 64 => 52 => 29 => 85 => 89 => 145 => 42 > => 20 => 4 => 16 => 37 => 58 => 89, at which point we have a cycle (89 > appeared twice). > > But 7 IS happy in base 10: 7 => 49 => 97 => 130 => 10 => 1 > > On Sep 12, 1:18 am, Mahendra Kariya <mahendrakar...@gmail.com> wrote: >> I guess in the first ques of Round 1A, we have to check only until the sum >> of squares of digits is not a single digit integer. Say, for sum number, >> if >> we get the sum of square of digits 8, we stop there and declare it to be >> unhappy without doing 8*8 = 64 . >> >> Regards, >> Mahendra Kariyahttp://www.mahendrakariya.blogspot.com > > > -- Sent from my mobile device --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "google-codejam" group. To post to this group, send email to google-code@googlegroups.com To unsubscribe from this group, send email to google-code+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/google-code?hl=en -~----------~----~----~----~------~----~------~--~---
