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
1 1
1 2 1
1 3 3 1
1 4 6 4 1
etc.
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 2^{n} 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 selfcontained
 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.
