java - how to make collapse number with hypen -

java - how to make collapse number with hypen -

i want create number in collapse format hypen symbol.

suppose input "1,2,4,6,7,8,9,11,12,14,16,17,18,19"

and want output below "1-2,4,6,7-9,11-12,14,16-19

this sounds homework question me, i'll @ to the lowest degree point in right direction.

personally utilize stringtokenizer , split string integer array. loop through array , checking if contents of current position related next position or not, find way save values , print them later. might require sec loop print later, think creative , find solution faster single loop. ;)

if want fancy, might take recursion , seeing if can using single function , string.

hope find helpful , sends in right direction.

java