#include <bits/stdc++.h>
using namespace std;
const double eps(1e-8);
const double pi(3.14159265358979);
const int N = 100100, mod = 1000000007;
int n, k;
long long d[N] = {1}, re[N] = {1, 1}, red[N] = {1, 1}, bp[N] = {1}, s[N] = {};
char ch[N] = {};
inline long long C(int n, int m) {
  return n < m || m < 0 ? 0ll : d[n] * red[m] % mod * red[n - m] % mod;
}
void init() {
  cin >> n >> k >> (ch + 1);
  for (int i = 1; i <= n; ++i) d[i] = (d[i - 1] * i) % mod;
  for (int i = 2; i <= n; ++i) {
    long long a = mod / i, b = mod % i;
    re[i] = ((-a * re[b]) % mod + mod) % mod;
    red[i] = (red[i - 1] * re[i]) % mod;
  }
  for (int i = 1; i <= n; ++i) bp[i] = (bp[i - 1] * 10) % mod;
}
void work() {
  for (int i = 1; i <= n; ++i)
    s[i] = (s[i - 1] + bp[i - 1] * C(n - i - 1, k - 1)) % mod;
  long long ans = 0;
  for (int i = 1; i <= n; ++i)
    ans += (s[n - i] + (bp[n - i] * C(i - 1, k)) % mod) * (ch[i] - '0') % mod;
  cout << ans % mod << endl;
}
int main() {
  init();
  work();
  return 0;
}
