#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 100, mod = 1e9 + 7;
int n, k;
string s;
long long t = 1, q, sum[N], f[N], tmp;
long long pw(long long x, long long y) {
  long long ans = 1, tm = x;
  while (y) {
    if (y & 1) ans = ans * tm;
    tm *= tm;
    tm %= mod;
    ans %= mod;
    y >>= 1;
  }
  return ans % mod;
}
long long w(int e, int r) {
  if (r > e) return 0;
  return ((f[e] * pw(f[r], mod - 2) % mod) * pw(f[e - r], mod - 2)) % mod;
}
int main() {
  ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  cin >> n >> k >> s;
  for (int i = 0; i < n; i++) sum[i + 1] = sum[i] + (s[i] - '0');
  f[0] = 1;
  for (int i = 1; i <= n + 1; i++) f[i] = (f[i - 1] * i) % mod;
  for (int i = 0; i < n; i++) {
    tmp = (w(n - i - 2, k - 1) * sum[n - i - 1]) % mod;
    tmp += ((w(n - i - 1, k) * (s[n - i - 1] - '0'))) % mod;
    tmp %= mod;
    tmp *= (pw(10, i));
    tmp %= mod;
    q += tmp;
    q %= mod;
  }
  cout << q;
}
