The first line contains a integer $T$ $(1 \leq T \leq 10)$, denoting the number of test cases.
In each test case, the first line are two integers $n, m$, denoting the number of cities and roads$(1\leq n\leq 100,000, 1\leq m\leq 200,000)$.
Then $m$ lines follow, each with two integers $u$ and $v$, which means there is a directed road from city $u$ to $v$ $(1\leq u, v\leq n, u \neq v)$.
The next line is a integer q, denoting the number of queries $(1\leq q\leq 100,000)$
And then $q$ lines follow, each with two integers $a$ and $b$, which means the two cities carrying out the critical task are $a$ and $b$ $(1\leq a, b\leq n, a \neq b)$.
A city is a command center if and only if there is no road from it (its out degree is zero).