cpp/algorithm/ranges/set difference

Copies the elements from the sorted input range which are not found in the sorted input range  to the output range beginning at.

The behavior is undefined if
 * the input ranges are not sorted with respect to and  or, respectively, or
 * the resulting range overlaps with either of the input ranges.

@1@ Elements are compared using the given binary comparison function.

@2@ Same as, but uses as the first range and  as the second range, as if using  as ,  as ,  as , and  as.

Return value
, where is the end of the constructed range.

Complexity
At most comparisons and applications of each projection, where  and  are  and, respectively.