Subtree swapping

You are given rooted tree with N weighted nodes numbered from 1 to N. The root of tree is node with number 1. Your goal is to handle Q queries, each of which can be one of the below three types: - getSum(u) := returns sum of values in nodes in u's subtree. - add(u, x) := adds x to values of every node in u's subtree (including u). - swap(u, v) := swaps whole subtrees of u and v if and only if t