result to store the minimum absolute difference, initially set to a large value.x and insert the elements into the multiset.size - x:
a. Use lower_bound to find the closest element in the multiset to the current element.
b. Update result with the minimum of the current result and the absolute difference between the current element and the lower_bound result.
c. If there is an element before the lower_bound result, update result with the minimum of the current result and the absolute difference between the current element and this previous element.
d. Remove the element that is x indices ahead of the current index from the multiset.result as the minimum absolute difference.