#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 5, P = 1e9 + 7;
int n, k, sum, fact[N] = {1}, inv[N] = {1};
inline int power(int a, int b) {
  int ans = 1;
  for (; b; a = 1LL * a * a % P, b >>= 1) ans = 1LL * ans * (b & 1 ? a : 1) % P;
  return ans;
}
inline int C(int a, int b) {
  return a < b ? 0 : 1LL * fact[a] * inv[b] % P * inv[a - b] % P;
}
int main() {
  string s;
  cin >> n >> k >> s;
  for (int i = 1; i <= n; i++)
    inv[i] = power(fact[i] = 1LL * fact[i - 1] * i % P, P - 2);
  for (int i = n - 1, cnt = 0; ~i; i--) {
    (cnt += (i < n - 1 ? 1LL * C(i, k - 1) * power(10, n - i - 2) % P : 0)) %=
        P;
    (sum += 1LL * (s[i] - '0') *
            (cnt + 1LL * C(i, k) * power(10, n - i - 1) % P) % P) %= P;
  }
  cout << sum;
}
