We have N colored balls arranged in a row from left to right; the color of the i-th ball from the left is c_i.
You are given Q queries. The i-th query is as follows: how many different colors do the l_i-th through r_i-th balls from the left have?

-----Constraints-----
- $1\leq N,Q \leq 5 \times 10^5$
- $1\leq c_i \leq N$
- $1\leq l_i \leq r_i \leq N$
- All values in input are integers.

-----Input-----
Input is given from Standard Input in the following format:
N Q
$c_1 c_2 \cdots c_N$
l_1 r_1
l_2 r_2
:
l_Q r_Q

-----Output-----
Print Q lines. The i-th line should contain the response to the i-th query.

-----Sample Input-----
4 3
1 2 1 3
1 3
2 4
3 3

-----Sample Output-----
2
3
1

• The 1-st, 2-nd, and 3-rd balls from the left have the colors 1, 2, and 1 - two different colors.
• The 2-st, 3-rd, and 4-th balls from the left have the colors 2, 1, and 3 - three different colors.
• The 3-rd ball from the left has the color 1 - just one color.

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