Integers arrive as '+x' (add one copy of x) and '-x' (remove every copy of x). After each query, count the triples of elements with values v, v+d and v+2d for a given d.

Start with an empty collection of integers, in which the same value may appear more than once, and a fixed difference d. Process a list of queries of two kinds: '+x' adds one copy of x, and '-x' removes every copy of x. After each query, count the triples of elements (x, y, z) in the collection with x - y = d and y - z = d, that is, three elements whose values are v, v + d and v + 2d. The position of the elements in the collection does not matter, and equal values are distinct elements, so if those three values occur a, b and c times they contribute a * b * c triples. Return the list of counts, one per query. All values lie between -10^9 and 10^9, a removal always names a value that is present, and every count fits in a 32-bit integer. Example with d = 5: the queries +5, +5, +0, +10, +10, -5 give 0, 0, 0, 2, 4, 0.