|Re: Live from HHC2009 (well, not quite live any more)|
Message #9 Posted by Jeff O. on 5 Oct 2009, 1:38 p.m.,
in response to message #7 by Don Shepherd
It was specific to the 50G:
HHC 2009 Programming Challenge
Finding partial sums of rows of Pascal's Triangle
1 2 1
1 3 3 1
1 4 6 4 1
Write an HP50g program which takes a positive integer n of any size in level 2 and any integer r in level 1 and returns the sum of C(n,0) + C(n,1)+...+C(n,r) to level 1. The output should be 0 for r<0 and 2n for r >= n.
The program will be transferred from your HP50g to the judges' HP50g and will be tested (in exact mode) for a selection of values of n and r chosen by the judges. The fastest program wins.
The usual rules apply:
- The program must be in user code only
- The program must be self-contained
- The program must leave the stack unchanged except for replacing n and r with the result.
- Default flag settings are assumed, except that RPN mode must be set. Flag settings must be restored if changed.
- The judges’ decision is final.