[Tutor] Memory error - how to manage large data sets?

[Chris Fuller]

There's no need to keep any lists.  The sum can be done on the fly, which is 
perhaps a bit slower, but takes a constant amount of ram.  Even storing every 
other element (or every third, which is what he's trying to do: the elements 
that are even numbers, not every other element.. See his example code, or 
Project Euler, problem two, which seems to be the original source) will still 
take a lot of ram.

Something like this:

a = 0
b = 1

total = 0

while True:
   c = a+b
   a = b
   b = c

  if c>1e6:
    break

  if c%2 == 0:
    total += c

print total

By the way,  working through those problems will really exercise your 
programming and math skills.  It's a great way to get started, if you enjoy 
those kind of puzzles.


Can you see why every third element must be even?
Cheers