Problem - Distance Queries - Read Statement

You need to answer distance queries between pairs of nodes in a tree. The distance is the number of edges on the path connecting them. The formula:

dist(u, v) = depth[u] + depth[v] - 2 * depth[lca(u, v)]

Preprocess the tree with binary lifting to answer LCA queries in $O(\log n)$ time, then compute distances using the formula. Try implementing this yourself. You already know binary lifting from the previous section.