question: public static List < Integer > createRanges ( int ... startEnds ) { assert startEnds . length % 2 == 0 ; ArrayList < Integer > ret = new ArrayList < Integer > ( ) ; for ( int si = 0 ; si < startEnds . length ; si ++ ) { final int start = startEnds [ si ++ ] ; final int end = startEnds [ si ] ; assert end >= start ; ret . ensureCapacity ( ret . size ( ) + ( ( end - start ) + 1 ) ) ; for ( int i = start ; i <= end ; i ++ ) { ret . add ( new Integer ( i ) ) ; } } return ret ; }
target:  Create a list of integers consisting of the ranges defined by the provided argument e.g.. createRanges(1, 4, 10, 12) means create ranges 1 through 4 and 10 through 12 and should yield the list: 1, 2, 3, 4, 10, 11, 12