#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define in(x) freopen(x, "r", stdin)
#define out(x) freopen(x, "w", stdout)
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("-O3")
#define F first
#define S second
#define pb push_back
#define N +100500
#define M ll(1e9 + 7)
#define sz(x) (int)x.size()
#define re return
#define oo ll(1e9)
#define el '\n'
#define pii pair <int, int>
using namespace std;
//using namespace __gnu_pbds;
//typedef tree <int, null_type, less_equal <int> , rb_tree_tag, tree_order_statistics_node_update> ordered_set;
typedef long long ll;
typedef long double ld;
int sf[N][26], i, n, q, len, fc[N], j, ans = 0;
string s, t;
int sum(int x, int y) {return (x + y) % M;}
int mult(int x, int y) {return (x * 1ll * y) % M;}
int bp(int x, int y)
{
if (y == 0) return 1;
if (y % 2) return (mult(x, bp(x, y - 1)));
int a = bp(x, y / 2);
return mult(a, a);
}
int C(int k, int n)
{
return c[n][k];
}
int main()
{
srand(time(0));
ios_base::sync_with_stdio(0);
iostream::sync_with_stdio(0);
ios::sync_with_stdio(0);
cin.tie(NULL);
cout.tie(NULL);
// in("input.txt");
// out("output.txt");
cin >> s;
cin >> q;
n = sz(s);
for (i = n - 1; i >= 0; i--)
{
for (j = 0; j < 26; j++) sf[i][j] = sf[i + 1][j];
sf[i][s[i] - 'a']++;
}
for (i = 0; i <= n; i++)
{
c[i][0] = c[i][n] = 1;
for (int j = 1; j < n; j++)
c[i][j] = sum(c[i - 1][j], c[i - 1][j - 1]);
}
while (q--)
{
cin >> len >> t;
ans = 0;
for (i = len - 2; i < n; i++)
{
if (s[i] == t[0])
{
ans = sum(ans, mult(C(len - 2, i), sf[i + 1][t[1] - 'a']));
}
}
cout << ans << el;
}
}
/*
8 8
...).).*
*....)..
.)*(..).
(*)((...
.)).)(..
.)(.)..(
...).(.*
M.......
*/
//
//110000
//1100
Compilation message
mate.cpp: In function 'int C(int, int)':
mate.cpp:41:12: error: 'c' was not declared in this scope
return c[n][k];
^
mate.cpp: In function 'int main()':
mate.cpp:69:9: error: 'c' was not declared in this scope
c[i][0] = c[i][n] = 1;
^
