Simple string manipulation (string)

Description

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Give you a string \(S\) with a length of \(n\) and only lowercase letters (subscripts start from \(1\) to \(n\)), perform the following two operations \(Q\) times:
1 i c: Replace the character at position \(i\) in the string \(S\) with the character \(c\);
2 l r: The number of different characters from the \(l\)th position to the \(r\)th position in the query string \(S\).

Format

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Input

The first line contains an integer \(n\), which represents the length of the string \(S\).
The second line contains a string \(S\) of length \(n\), containing only lowercase letters.
The third line contains an integer \(Q\), which represents the number of operations.
In line \(4 \sim Q+3\), each line describes one of the above two operations.

Output

For each operation \(2\), the output line contains an integer, which represents the number of different characters in \(S[l \dots r]\).

Sample

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Input

7
abcdbbd
6
2 3 6
1 5 z
2 1 1
1 4 a
1 7 d
2 1 7

Output

3
1
5

Hint

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\(\text{Subtask1(50%)}\)：\(1\le n \le 100\)；
\(\text{Subtask2(50%)}\)：\(1\le n \le 500000, 1 \le Q \le 20000\)。

Sample Code

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Code is not available!