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 Java8 (OpenJDK 1.8.0) (judge verdict: Time Limit Exceeded)

import java.util.*;
import java.io.*;

public class Main {
	private static void solve(){
	//Implement solution here.
		int n = ni();
		int q = ni();
		String s = next();
		char[] ca = s.toCharArray();
		
		int casum = 0;
		int[] enda = new int[n];
		
		char tmp = ca[0];		
		for(int i = 1; i < n; i++) {
			if(tmp == 'A' && ca[i] == 'C') {
				casum++;
			}
			enda[i] = casum;
			tmp = ca[i];
		}
		
		for(int i = 0; i < q; i++) {
			int l = ni();
			int r = ni();
			System.out.println(enda[r - 1] - enda[l - 1]);
		}
	}

    //Switch input source (stdin/file)
	private static Scanner scanner = new Scanner(System.in);
	public static void main(String[] args){
        String debugDataPath = System.getenv("DD_PATH");        
        if(debugDataPath != null){
            try{
                scanner = new Scanner(new BufferedReader(new InputStreamReader(new FileInputStream(new File(debugDataPath)))));
            }catch(Exception e){
                throw new RuntimeException(e);
            }
        }
        solve();
	}

    //Input read utility
	private static StringTokenizer tokenizer = null;
	public static String next() {
		while (tokenizer == null || !tokenizer.hasMoreTokens()) {
			try {
				tokenizer = new StringTokenizer(scanner.nextLine());
			} catch (Exception e) {
				throw new RuntimeException(e);
			}
		}
		return tokenizer.nextToken();
	}
    //Get next single int
	private static int ni() {
		return Integer.parseInt(next());
	}
    //Get next single long
	private static long nl() {
		return Long.parseLong(next());
	}
    //Get next single double
	private static double nd() {
		return Double.parseDouble(next());
	}
    //Get next int array from one line
	private static int[] na(int n) {
		int[] a = new int[n];
		for (int i = 0; i < n; i++)
			a[i] = ni();
		return a;
	}
	//Get next char array from one line
	private static char[] ns() {
		return next().toCharArray();
	}
    //Get next long array from one line
	private static long[] nal(int n) {
		long[] a = new long[n];
		for (int i = 0; i < n; i++)
			a[i] = nl();
		return a;
	}
}