You are given a string S of length N consisting of lowercase English letters.

Process Q queries of the following two types:

• Type 1: change the i_q-th character of S to c_q. (Do nothing if the i_q-th character is already c_q.)
• Type 2: answer the number of different characters occurring in the substring of S between the l_q-th and r_q-th characters (inclusive).

Constraints

• N, Q, i_q, l_q, and r_q are integers.
• S is a string consisting of lowercase English letters.
• c_q is a lowercase English letter.
• $1 \leq N \leq 500000$
• $1 \leq Q \leq 20000$
• |S| = N
• $1 \leq i_q \leq N$
• $1 \leq l_q \leq r_q \leq N$
• There is at least one query of type 2 in each testcase.

Input

Input is given from Standard Input in the following format:

N
S
Q
Query_1
$\vdots$
Query_Q

Here, Query_i in the 4-th through (Q+3)-th lines is one of the following:

1 i_q c_q

2 l_q r_q

Output

For each query of type 2, print a line containing the answer.

Example

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

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