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 C# (Mono 4.6.2.0) (judge verdict: Time Limit Exceeded)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

public static partial class Program
{
    //テンプレここから
    public static int ToInt(this string str) => int.Parse(str);
    public static long ToLong(this string str) => long.Parse(str);
    public static int[] ToInt(this string[] strs) => strs.Select(x => x.ToInt()).ToArray();
    public static long[] ToLong(this string[] strs) => strs.Select(x => x.ToLong()).ToArray();
    public static int[] SpInts(this string str, char opr = ' ') => str.Split(opr).ToInt();
    public static long[] SpLongs(this string str, char opr = ' ') => str.Split(opr).ToLong();
    public static string CRL() => Console.ReadLine();
    public static void CWL(object obj) => Console.WriteLine(obj);
    public static int Diff(int a, int b) => (int)Diff(a, (long)b);
    public static long Diff(long a, long b) => Math.Abs(Math.Max(a, b) - Math.Min(a, b));
    public static int Sign(this int i) => Math.Sign(i);
    public static bool IsEven(this int i) => i % 2 == 0;
    public static int[] dx = new int[] { 0, -1, 0, 1 };
    public static int[] dy = new int[] { -1, 0, 1, 0 };
    public static int Gcd(int a, int b) => (int)Gcd(a, (long)b);
    public static long Gcd(long a, long b)
    {
        if (b == 0)
        {
            return a;
        }

        return Gcd(b, a % b);
    }                       //最大公約数
    public static int Lcm(int a, int b) => (int)Lcm(a, (long)b);
    public static long Lcm(long a, long b) => a / Gcd(a, b) * b;    //最小公倍数
    //テンプレここまで
}

public static partial class Program
{
    public static void Main()
    {
        var nq = CRL().SpInts();
        var n = nq[0];
        var q = nq[1];
        var s = CRL();
        for (int i = 0; i < q; i++)
        {
            var lr = CRL().SpInts();
            var l = lr[0];
            var r = lr[1];

            var str = s.Substring(l - 1, r - l + 1);
            CWL(Regex.Matches(str, "AC").Count);
        }
    }
}