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 Python (3.4.3) (judge verdict: Accepted)

from collections import Counter 
from collections import defaultdict
from collections import deque
from functools import reduce
import math
import itertools
import heapq
import numpy as np
import bisect
import sys
#import sympy
sys.setrecursionlimit(10**6)


def bfs(s,n,node):
    #頂点が探索済みかどうかのチェック配列
    check=[False for _ in range(n)]
    check[s]=True
    #次見る頂点を格納するキュー
    queue=deque([s])
    visited_num=1

    #問題固有の配列
    #color_check=[[True for _ in range(l)] for _ in range(n)]
    color=[-1 for _ in range(n)]
    color[s]=0
    
    while visited_num<n:
        #グラフが全連結ではない場合
        if len(queue)==0:
            #空配列を返す
            #現状までの計算済み配列を返してもいいと思う
            return color

        now_vertex=queue.popleft()
        #インデックスがない場合は
        for next_vertex in node[now_vertex]:


            if check[next_vertex]==True:
                continue

            queue.append(next_vertex)
            check[next_vertex]=True

            #問題固有の計算
            color[next_vertex]=color[now_vertex]+1
            visited_num+=1

    return color

#n=int(input())z
#n,m=list(map(int,input().split()))
#a=list(map(int,input().split()))
ceil=lambda x,y: (x+y-1)//y
input_list = lambda : list(map(int,input().split()))

n,q=input_list()
s=input()
l=len(s)
left=[0 for _ in range(l)]
for i in range(1,l):
    left[i]=left[i-1]
    if s[i-1]+s[i]=="AC":
        left[i]+=1

for _ in range(q):
    l,r=input_list()
    print(left[r-1]-left[l-1])