Problem7641--[CSES Problem Set] Palindrome Queries

7641: [CSES Problem Set] Palindrome Queries

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Time Limit : 1.000 sec  Memory Limit : 256 MiB

Description

You are given a string that consists of $n$ characters between a–z. The positions of the string are indexed $1,2,\dots,n$.
Your task is to process $m$ operations of the following types:
  1. Change the character at position $k$ to $x$
  2. Check if the substring from position $a$ to position $b$ is a palindrome

Input

The first input line has two integers $n$ and $m$: the length of the string and the number of operations.
The next line has a string that consists of $n$ characters.
Finally, there are $m$ lines that describe the operations. Each line is of the form "1 k x" or "2 a b".

Output

For each operation 2, print YES if the substring is a palindrome and NO otherwise.

Constraints

$1≤n,m≤2⋅10^5$
$1 \le k \le n$
$1 \le a \le b \le n$

Sample 1 Input

7 5
aybabtu
2 3 5
1 3 x
2 3 5
1 5 x
2 3 5

Sample 1 Output

YES
NO
YES

HINT

相同题目:CSES 2420

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