write a go solution for Description:
For a given set of two-dimensional points S, let's denote its extension E(S) as the result of the following algorithm:

Create another set of two-dimensional points R, which is initially equal to S. Then, while there exist four numbers x_1, y_1, x_2 and y_2 such that (x_1,y_1)inR, (x_1,y_2)inR, (x_2,y_1)inR and (x_2,y_2)notinR, add (x_2,y_2) to R. When it is impossible to find such four integers, let R be the result of the algorithm.

Now for the problem itself. You are given a set of two-dimensional points S, which is initially empty. You have to process two types of queries: add some point to S, or remove some point from it. After each query you have to compute the size of E(S).

Input Format:
The first line contains one integer q (1<=q<=3*10^5) — the number of queries.

Then q lines follow, each containing two integers x_i, y_i (1<=x_i,y_i<=3*10^5), denoting i-th query as follows: if (x_i,y_i)inS, erase it from S, otherwise insert (x_i,y_i) into S.

Output Format:
Print q integers. i-th integer should be equal to the size of E(S) after processing first i queries.

Note:
None. Output only the code with no comments, explanation, or additional text.