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So I have a bunch of c(start,end) points and want to consolidate them into as few c(start,end) as possible. For example: sample start end A 5 10 B 7 18 C 1 4 D 16 20 I'd want the function to return the two distinct sets (1,4) and (5,20) Is there an R function that already does this? or should I write my own?