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)]
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
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 time |
Memory |
Grader output |
1 |
Runtime error |
37 ms |
12424 KB |
Execution failed because the return code was nonzero |
2 |
Runtime error |
47 ms |
12476 KB |
Execution failed because the return code was nonzero |
3 |
Runtime error |
37 ms |
12548 KB |
Execution failed because the return code was nonzero |
4 |
Runtime error |
37 ms |
12712 KB |
Execution failed because the return code was nonzero |
5 |
Runtime error |
38 ms |
12968 KB |
Execution failed because the return code was nonzero |
6 |
Runtime error |
37 ms |
12968 KB |
Execution failed because the return code was nonzero |
7 |
Runtime error |
39 ms |
13048 KB |
Execution failed because the return code was nonzero |
8 |
Runtime error |
37 ms |
13048 KB |
Execution failed because the return code was nonzero |
9 |
Runtime error |
39 ms |
13204 KB |
Execution failed because the return code was nonzero |
10 |
Runtime error |
38 ms |
13236 KB |
Execution failed because the return code was nonzero |