Submission #83583

#	Time	Username	Problem	Language	Result	Execution time	Memory
83583		XBXJLeiLeLeiLe	Mate (COCI18_mate)	Pypy 2	0 / 100	39 ms	11728 KiB

mate

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
    for i in range(k):
        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] * 26
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


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

• Subtask 1: 0 / 100