제출 #83629

#제출 시각아이디문제언어결과실행 시간메모리
83629charlies_mooMate (COCI18_mate)Pypy 2
0 / 100
2074 ms20980 KiB
s = raw_input()
q = input()


def combination(n, d):
    k = d - 2
    if n - k < k:
        k = n - k
    result = 1
    for i in range(k):
        result *= n
        n -= 1
    w = k
    for i in range(w):
        result /= k
        k -= 1
    return result


def mod(num):
    return num % (10**9+7)


def lst_id(letter):
    return ord(letter) - ord("a")



arr = [[0 for i in range(26)] for i in range(len(s))]
arr_c = [0 for i in range(26)]



try:
    for i in range(len(s)-1, -1, -1):
        for j in range(26):
            arr[i][j] = arr_c[j]
        arr_c[lst_id(s[i])] += 1

except:
    pass


    arr_r = []
    for i in range(q):
        d, xy = raw_input().split()
        total = 0
        d = int(d)
        x = xy[0]
        y = xy[1]
        for i in range(len(s)):
            if s[i] == x and i >= d - 2:
                total += combination(i, d) * arr[i][lst_id(y)]
        arr_r.append(mod(total))

    for ans in arr_r:
        print ans

#Verdict Execution timeMemoryGrader output
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