P7477 "C.E.L.U-02" Partitioning a Multiset

You are given a sequence $v$ of length $n$. Please partition it into two multisets $a$ and $b$. You will partition from left to right, and each number must be put into at least one multiset. A number $v_i$ can be put into $a$ if and only if all $v_j$ with $j

The first line contains two integers $n,m$, as described in the statement. The next line contains $n$ integers, representing $v$. The following $m$ lines each contain two integers, representing one relation.

Output one integer, the answer.

### Sample Explanation **Sample Explanation 1** The following is one valid partition: |6|2|8|5|7|3| |:---:|:---:|:---:|:---:|:---:|:---:| |a|b|b|a|b|a| **Sample Explanation 2** The following is one valid partition: |1|3|4|3|8|2|3|4|5|6| |:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:|:---:| |b|b|a|b|a|b|a|a|a|b| ### Constraints |Test ID|$n$|$m$| |:---:|:---:|:---:| |$1\sim2$|$\le10^3$|$0$| |$3\sim4$|$\le10^3$|$\le10^3$| |$5\sim6$|$\le2\times10^4$|$0$| |$7\sim10$|$\le2\times10^4$|$\le2\times10^4$| For $100\%$ of the testdata, $n,m\le2\times10^4$ and $v_i\le10^9$. It is guaranteed that $u