Problem:
Score : 300 points

Problem Statement

You are given a string S of length N consisting of A, C, G and T. Answer the following Q queries:

Query i (1 \leq i \leq Q): You will be given integers l_i and r_i (1 \leq l_i < r_i \leq N). Consider the substring of S starting at index l_i and ending at index r_i (both inclusive). In this string, how many times does AC occurs as a substring?

Notes

A substring of a string T is a string obtained by removing zero or more characters from the beginning and the end of T.

For example, the substrings of ATCODER include TCO, AT, CODER, ATCODER and (the empty string), but not AC.

Constraints

2 \leq N \leq 10^5

1 \leq Q \leq 10^5

S is a string of length N.

Each character in S is A, C, G or T.

1 \leq l_i < r_i \leq N

Input

Input is given from Standard Input in the following format:

N Q
S
l_1 r_1
:
l_Q r_Q

Output

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

Sample Input 1

8 3
ACACTACG
3 7
2 3
1 8

Sample Output 1

2
0
3

Query 1: the substring of S starting at index 3 and ending at index 7 is ACTAC. In this string, AC occurs twice as a substring.

Query 2: the substring of S starting at index 2 and ending at index 3 is CA. In this string, AC occurs zero times as a substring.

Query 3: the substring of S starting at index 1 and ending at index 8 is ACACTACG. In this string, AC occurs three times as a substring.

Solution in Kotlin (1.0.0) (judge verdict: Time Limit Exceeded)

import java.io.BufferedReader
import java.io.InputStreamReader
import java.io.PrintWriter

val br = BufferedReader(InputStreamReader(System.`in`))
val pw = PrintWriter(System.out)
fun main(args : Array<String>) {
    func()
    pw.flush()
}

fun func() {
    // 回答をここに書く
    val (n, q) = listOfInt()
    val s = next()
    val hoge = s.mapIndexedNotNull{ k, v ->
        if((v.toString()+s.getOrNull(k+1).toString()) == "AC") {
            k+1 to 1
        }else k+1 to 0
    }.toMap()
    (1..q).forEach {
        val (l, r) = listOfInt()
        val sum = (l..r).asSequence().map {
            if(it != r) hoge[it] ?: 0 else 0
        }.sum()
        println(sum)
    }
}

// 入力取得
fun next() = br.readLine()!!
fun nextInt() = next().toInt()
fun nextLong() = next().toLong()
fun nextDouble() = next().toDouble()
fun listOfString() = next().split(" ")
fun listOfInt() =listOfString().map { it.toInt() }
fun listOfLong() =listOfString().map { it.toLong() }
fun listOfDouble() =listOfString().map { it.toDouble() }

// 約数のList
fun divisor(value : Long) : List<Long> {
    val max = Math.sqrt(value.toDouble()).toLong()
    return (1..max)
            .filter { value % it == 0L }
            .map { listOf(it, value / it) }
            .flatten()
            .sorted()
}

// 範囲内の素数を取得
// fromだけ指定すると戻り値の個数で素数判定ができる
fun prime(from : Long, to : Long = from) : List<Long> {
    return (from..to).filter { i ->
        val max = Math.sqrt(i.toDouble()).toLong()
        (2..max).all { j ->  i % j != 0L }
    }
}

// 素因数分解
fun decom(value : Long) : List<Long>{
    if (value == 1L) return listOf(1)
    val max = Math.sqrt(value.toDouble()).toLong()
    return prime(2, max).filter { value % it == 0L }
}

// 最大公約数
fun gcd(a : Long, b : Long) : Long {
    return if (a % b == 0L) b else gcd(b, a % b)
}

// 文字列を入れ替え
fun swap(base : String, a : String, b : String) : String {
    return base.map {
        when (it) {
            a.toCharArray()[0] -> b
            b.toCharArray()[0] -> a
            else -> it.toString()
        }
    }.joinToString()
}

fun println(value : Any) {
    pw.println(value)
}