P9361 [ICPC 2022 Xi'an R] Contests

There are $n$ contestants and they take part in $m$ contests. You are given the ranklist of each contest. The ranklist of the $k$-th contest is a sequence $a_k$, indicating that the $a_{k, i}$-th contestant's rank is $i$. SolarPea and PolarSea are two of the $n$ contestants. SolarPea wants to prove that he is stronger than PolarSea. Define $x$ is $l$-stronger than $y$, if and only if there exists a sequence $b$ of length $l + 1$, such that $b_1 = x$, $b_{l + 1} = y$, and for all $1\leq i\leq l$, $b_i$ has a smaller rank than $b_{i + 1}$ in at least one contest. There are $q$ queries. In the $i$-th query, SolarPea is contestant $x$ and PolarSea is contestant $y$. Please find the minimum positive number $l$ such that SolarPea is $l$-stronger than PolarSea.

The first line contains two integers $n$ ($2\leq n\leq 10 ^ 5$) and $m$ ($1\leq m\leq 5$). The $i$-th of the next $m$ lines contains $n$ intergers $a_{i, 1}, a_{i, 2}, \ldots, a_{i, n}$. It is guaranteed that $a_i$ is a permutaion of $1,2,\ldots,n$. The next line contains an integer $q$ ($1\leq q\leq 10 ^ 5$). Each of the next $q$ lines contains two integers $x$ and $y$ ($1 \le x,y \le n, x \neq y$), representing a query.

For each query, output a number $l$ representing the answer. If there is no legal $l$, output $-1$.

**Source**: The 2022 ICPC Asia Xi'an Regional Contest Problem D. **Author**: csy2005.