Removing elements from a very large list?

Hi,

I have 2 very large lists (one has over 40,000 elements and the other approx 1/2 that). The list elements contain IDs so only 2-6 ints per element.

I want to remove all the elements of the smaller list from the bigger list so I need to with a third list which will A-B=C (I hope that makes sense).

This is a one function... What is the best way to do this please?

Thanks

 

you could probably find a faster way to do this but..

<cfloop list="#a#" index="alist">
<cfif NOT listfind(b,"#alist#")>
<cfset temp=listappend(c,"#alist#")>
</cfif>
</cfloop>

for the size of the lists i doubt this is the best method.. but if you're in need of a temporary solution this should work..

 

That worked great thanks..

 

First place I check for this kind of thing is www.cflib.org. Most times whatever I'm trying to do ... they've got a function for that

Their String library has a bunch of list functions
http://www.cflib.org/library.cfm?ID=1