Dense Graph

You are given an unweighted directed graph with $N$ vertices (numbered $1$ through $N$). You are also given $2M$ ranges $[A_1, B_1], [A_2, B_2], \ldots, [A_M, B_M]$ and $[C_1, D_1], [C_2, D_2], \ldots, [C_M, D_M]$ describing the edges of the graph in the following way: For each $i$ ($1 \le i \le M$) and for each pair of vertices $u \in [A_i, B_i]$, $v \in [C_i, D_i]$, there is an edge from $u$ to