Build a Number Range

Hi Experts,

I have been unable to do this and hoping somebody can help!  I have the following string of comma delimited numbers and that I need to breakdown and display as a range.

String: 1,2,3,4,6,7,8,9,10,11,12,15,19,21,22

Display as: 1-4, 6-12, 15, 19, 21-22

Any help would be greatly appreciated,

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_agx_Connect With a Mentor Commented:
<!--- always sort first so the ranges make sense --->
<cfset numbers = listToArray("1,2,3,4,6,7,8,9,10,11,12,15,19,21,22")>
<cfset arraySort(numbers, "numeric")>

<cfset startAt = 1>
<cfset maxPosition = arrayLen(numbers)>
<cfset ranges = []>

<cfloop from="1" to="#maxPosition#" index="pos">
        <!--- check difference between current and next number --->
	<cfset offset = pos lt maxPosition ? 1 : 0>
	<cfset gap = numbers[pos+offset] - numbers[pos]>

	<!--- there was a jump in sequence OR this is the last element --->
	<cfif gap gt 1 OR pos eq maxPosition>
		<cfif startAt lt pos>
			<!--- range --->
			<cfset arrayAppend(ranges, numbers[startAt] &"-"& numbers[pos])>
			<!--- single value --->
			<cfset arrayAppend(ranges, numbers[pos])>
		<cfset startAt = pos + 1>

List of Ranges: <cfdump var="#arrayToList(ranges, ',')#">

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ehart12Author Commented:
Hi _agx_,

Once again, thank you the above solution!  What would be the best way to apply some type of numberformat so the actual format is as follows (three places with leading 0 to fill);

Is:  1-4, 6-12, 15, 19, 21-22

Desired: 001-004, 006-012, 015, 019, 021-022

Thank you,

It's probably simplest to do it before adding the values to the array. Totally untested, but something along these lines

      <cfif startAt lt pos>
            <!--- range --->
                <cfset fromValue = NumberFormat( numbers[startAt] , "000")>
                <cfset toValue = NumberFormat( numbers[pos] , "000")>
            <cfset arrayAppend(ranges, fromValue  &"-"& toValue )>
            <!--- single value --->
            <cfset arrayAppend(ranges,  NumberFormat(numbers[pos], "000"))>
ehart12Author Commented:
Excellent, thank you!
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