P3156 [Shenji 15. Example 1] Query Student ID Numbers

There are $n(n \le 2 \times 10^6)$ students entering the classroom one after another. We know each student’s ID number (between $1$ and $10^9$), given in the order they enter the classroom. Class starts, and the teacher wants to know what the ID number of the $i$-th student who entered the classroom is (the first student to enter has $i=1$). The number of queries does not exceed $10^5$.

The first line contains $2$ integers $n$ and $m$, representing the number of students and the number of queries. The second line contains $n$ integers, representing the ID numbers in the order they enter the classroom. The third line contains $m$ integers, representing queries asking for which student (by entry order) to check.

Output $m$ integers as the answers, separated by newlines.

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