#include <bits/stdc++.h>
using namespace std;
const int p = 1e9 + 7;
long long pm(long long a, long long n = p - 2) {
  long long r = 1;
  for (; n; n >>= 1, a = a * a % p)
    if (n & 1) r = r * a % p;
  return r;
}
char s[102400];
int n, k;
long long f[102400], r[102400];
long long C(int n, int m) {
  return m <= n ? f[n] * r[m] % p * r[n - m] % p : 0;
}
int main() {
  scanf("%d%d ", &n, &k);
  for (int j = n - 1; j >= 0; --j) scanf("%c", s + j);
  long long ans = 0, s = 0, d = 1;
  f[0] = r[0] = 1;
  for (int i = 1; i <= n; ++i) {
    f[i] = f[i - 1] * i % p;
    r[i] = pm(f[i]);
  }
  for (int i = 0; i < n; ++i, d = d * 10 % p) {
    ans = (ans + (C(n - i - 1, k) * d + s) % p * (::s[i] - '0')) % p;
    s = (s + d * C(n - i - 2, k - 1)) % p;
  }
  printf("%d\n", (int)ans);
}
