Very cool - I'm going to take a look at this. Thanks! And thanks to all for the feedback.
To answer the question as to why this problem came up in the first place - its exactly the reason that Ian mentioned. The challenge I was given was essentially: If you knew that the next lottery ticket would contain a value from a given set - how many lottery tickets would you need to purchase? - Ken On 9/26/07, Brian Swartzfager <[EMAIL PROTECTED]> wrote: > > Hi, Ken, > > I recently had to build a permutation generator to generate all the unique > combinations of a set of > > data where (just as in your case) order was not a factor. So given the > data set "A,B,C", I needed > > to get out: > > A,B,C > A,B > B,C > A,C > A > B > C > > I looked at my code and was able to modify it to (hopefully) suit your > purpose. It requires using recursion, so most of the work is done in a CFC > function. > > Here's the code for the CFC: > > <cfcomponent displayname="Permutations" hint="I generate the > permutations." > output="false"> > > <cffunction name="generatePermutations" output="true" > returntype="string" hint="I return a list of all possible combinations of a > list of items where the order of the items is constant but one or more items > can be missing"> > <cfargument name="starting_list" type="string" required="yes" > hint="The starting list of items. The list will grow smaller via > recursion." /> > <cfargument name="permutation_list" type="string" required="yes" > hint="The current list of permutations, which will grow longer." /> > <cfargument name="start_delimiter" type="string" required="yes" > hint="The list delimiter." /> > <cfargument name="perm_delimiter" type="string" required="yes" > hint="The delimiter for the final list. Should be different from > start_delimiter" /> > <cfset var temp= ""> > <cfset var p_list= arguments.permutation_list> > > <!---Determine if the full list of items is already in the > permutations list. If not, add it---> > <cfif Not ListFind(p_list,arguments.starting_list, > arguments.perm_delimiter) AND ListLen(arguments.starting_list,",") EQ 6> > <cfset p_list= ListAppend(p_list,arguments.starting_list, > arguments.perm_delimiter)> > </cfif> > > <!---If starting_list length is not 6, loop and call the function > for each iteration of the loop---> > <cfif ListLen(arguments.starting_list,arguments.start_delimiter) > GT 6> > <cfloop index="gone" from="1" to="#ListLen( > arguments.starting_list,arguments.start_delimiter)#"> > <cfset temp= ListDeleteAt(arguments.starting_list > ,gone,arguments.start_delimiter)> > <cfinvoke component="Permutations" > method="generatePermutations" returnvariable="p_list" starting_list="#temp#" > permutation_list="#p_list#" start_delimiter="#arguments.start_delimiter#" > perm_delimiter="#arguments.perm_delimiter#"></cfinvoke> > </cfloop> > </cfif> > > <cfreturn p_list /> > > </cffunction> > > </cfcomponent> > > > ....And here's the code for a page that you can use to test it: > > <cfsetting requesttimeout="600"> > <cfoutput> > > <cfset inputValues1= '1,2,3,4,5,6,7,'> > <cfset inputValues2= '1,2,3,4,5,6,7,8,9,10,11,12'> > > <p> > inputValues1 is: #inputValues1# > </p> > > <cfinvoke component="Permutations" method="generatePermutations" > starting_list="#inputValues1#" permutation_list="" start_delimiter="," > perm_delimiter="|" returnvariable="fullPermutationList"></cfinvoke> > > <p>List the permutations:</p> > <ul> > <cfloop index="combo" list="#fullPermutationList#" > delimiters="|"> > <li>#combo#</li> > </cfloop> > </ul> > > </cfoutput> > > > ....It can render your "1,2,3,4,5,6,7" example pretty quickly, but it > takes a pretty long time to do something larger like a 12-item set (hence > the <cfsetting> tag to increase the timeout), and I didn't have the time to > figure out how much time it would take to process a full 20-item list. > > Maybe there's a better way to do it, but hopefully this at least provides > a starting point. > > -- > Brian Swartzfager > [EMAIL PROTECTED] > > > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Get the answers you are looking for on the ColdFusion Labs Forum direct from active programmers and developers. http://www.adobe.com/cfusion/webforums/forum/categories.cfm?forumid-72&catid=648 Archive: http://www.houseoffusion.com/groups/CF-Talk/message.cfm/messageid:289698 Subscription: http://www.houseoffusion.com/groups/CF-Talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4
