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**Task** | Statistics

Time limit: | 1.00 s | Memory limit: | 512 MB |

A company has $n$ employees, who form a tree hierarchy where each employee has a boss, except for the general director.

Your task is to process $q$ queries of the form: who is employee $x$'s boss $k$ levels higher up in the hierarchy?

The first input line has two integers $n$ and $q$: the number of employees and queries. The employees are numbered $1,2,\dots,n$, and employee $1$ is the general director.

The next line has $n-1$ integers $e_2,e_3,\dots,e_n$: for each employee $2,3,\dots,n$ their boss.

Finally, there are $q$ lines describing the queries. Each line has two integers $x$ and $k$: who is employee $x$'s boss $k$ levels higher up?

Print the answer for each query. If such a boss does not exist, print $-1$.

- $1 \le n,q \le 2 \cdot 10^5$

- $1 \le e_i \le i-1$

- $1 \le x \le n$

- $1 \le k \le n$

Input:

`5 3`

1 1 3 3

4 1

4 2

4 3

Output:

`3`

1

-1