Buggy python submission (verdict: Runtime Error):
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
 
def main():
    n, q = map(int, readline().split())
    s = readline().rstrip().decode()
    ac = []    
    cnt = 0
    for i in range(1, n+1):
        if (s[i-1] == 'A') and (s[i] == 'C'):
            cnt += 1
            ac.append(cnt)
        else:
            ac.append(cnt)
    query = []
    for _ in range(q):
        l, r = map(int, readline().split())
        l -= 1
        r -= 1
        print(ac[r]-ac[l])
if __name__ == '__main__':
    main()


Fixed submission:
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
 
def main():
    n, q = map(int, readline().split())
    s = readline().rstrip().decode()
    ac = [0]    
    cnt = 0
    for i in range(1, n):
        if (s[i-1] == 'A') and (s[i] == 'C'):
            cnt += 1
            ac.append(cnt)
        else:
            ac.append(cnt)
    query = []
    for _ in range(q):
        l, r = map(int, readline().split())
        l -= 1
        r -= 1
        print(ac[r]-ac[l])
if __name__ == '__main__':
    main()

Buggy python submission (verdict: Runtime Error):
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
 
def main():
    n, q = map(int, readline().split())
    s = readline().rstrip().decode()
    ac = []    
    cnt = 0
    for i in range(n+1):
        if (s[i-1] == 'A') and (s[i] == 'C'):
            cnt += 1
            ac.append(cnt)
        else:
            ac.append(cnt)
    query = []
    for _ in range(q):
        l, r = map(int, readline().split())
        l -= 1
        r -= 1
        print(ac[r]-ac[l])
if __name__ == '__main__':
    main()


Fixed submission:
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
 
def main():
    n, q = map(int, readline().split())
    s = readline().rstrip().decode()
    ac = [0]    
    cnt = 0
    for i in range(1, n):
        if (s[i-1] == 'A') and (s[i] == 'C'):
            cnt += 1
            ac.append(cnt)
        else:
            ac.append(cnt)
    query = []
    for _ in range(q):
        l, r = map(int, readline().split())
        l -= 1
        r -= 1
        print(ac[r]-ac[l])
if __name__ == '__main__':
    main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
 
def main():
    n, q = map(int, readline().split())
    s = readline().rstrip().decode()
    
    for _ in range(q):
        l, r = map(int, readline().split())
        print(s[l-1:r].count('AC'))
if __name__ == '__main__':
    main()


Fixed submission:
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
 
def main():
    n, q = map(int, readline().split())
    s = readline().rstrip().decode()
    ac = [0]    
    cnt = 0
    for i in range(1, n):
        if (s[i-1] == 'A') and (s[i] == 'C'):
            cnt += 1
            ac.append(cnt)
        else:
            ac.append(cnt)
    query = []
    for _ in range(q):
        l, r = map(int, readline().split())
        l -= 1
        r -= 1
        print(ac[r]-ac[l])
if __name__ == '__main__':
    main()