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

**Input**

The first input line has two integers $n$ and $q$: the number of values and queries.

The second line has $n$ integers $x_1,x_2,\dots,x_n$: the array values.

Finally, there are $q$ lines describing the queries. Each line has two integers $a$ and $b$: what is the xor sum of values in range $[a,b]$?

**Output**

Print the result of each query.

**Constraints**

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

- $1 \le x_i \le 10^9$

- $1 \le a \le b \le n$

**Example**

Input:

`8 4`

3 2 4 5 1 1 5 3

2 4

5 6

1 8

3 3

Output:

`3`

0

6

4