This is an interactive problem.
You are given a directed graph $G$ on vertices numbered $0$ to $n$. Initially, $G$ contains exactly $n$ edges of the form $v \to v + 1$. Your task is to add some edges to this graph in such a way that for every two vertices $v, u$ ($v < u$) there exists a directed path from $v$ to $u$ consisting of at most three edges. There are also two additional requirements you must meet: