eduardische's blog

By eduardische, 6 years ago, translation, , Just as reminder, the round is scheduled at 16:00 UTC. Top 1000 contestants advance to Round 2. 2013, Comments (4)
 » 6 years ago, # | ← Rev. 2 →   I've solved problem B large but got Wrong Answer because of silly problem my codewhen I divide my long double-type variable by 2 million times it becomes too small and tend to zero after that when I multiply it by some numbers it still zero.actully what I wanted to compute is [ C(n,k)+C(n,k+1)+C(n,k+2) .... + C(n,n) ] / 2^n for some numbers n,kfails large input file but my algorithm is correct.
•  » » What I did was compute c(n,k)=C(n,k)/2^n in a table of doubles. The combination of multiplication and division by large doubles can be tricky, so it's good practice not to use it — most of the time, it can be replaced by simple multiplication and summation.
 » I played with Google Charts and made the following map: Google CodeJam 1st round statistics. It's just an experiment to learn Google Charts for this occasion. It shows 1000 * Round2 / (Round1A + Round1B) taken from Google CodeJam Statisics.
•  » » Single person statistics can be kinda tricky, if you notice the blue countries... good job anyway