#include <bits/stdc++.h>
using namespace std;
const int N = 100500;
const int MOD = 1e9 + 7;
long long fact[N], inv_fact[N];
long long cnk(int n, int k) {
  if (k > n) return 0;
  long long ret = fact[n];
  ret = (ret * inv_fact[k]) % MOD;
  ret = (ret * inv_fact[n - k]) % MOD;
  return ret;
}
long long bin_pow(long long a, long long w) {
  long long ret = 1;
  while (w) {
    if (w & 1) ret = (ret * a) % MOD;
    a = (a * a) % MOD;
    w >>= 1;
  }
  return ret;
}
void init() {
  fact[0] = inv_fact[0] = 1;
  for (int i = 1; i < N; i++) {
    fact[i] = (fact[i - 1] * i) % MOD;
    inv_fact[i] = (inv_fact[i - 1] * bin_pow(i, MOD - 2)) % MOD;
  }
}
int pref_sum[N];
int main() {
  init();
  int n, k;
  string s;
  cin >> n >> k;
  cin >> s;
  if (k == 0) {
    long long tt = 0;
    for (int i = 0; i < s.size(); i++) {
      tt = (tt * 10 + s[i] - '0') % MOD;
    }
    cout << tt << endl;
    return 0;
  }
  for (int i = 0; i < n; i++) {
    pref_sum[i] = s[i] - '0';
    if (i > 0) pref_sum[i] += pref_sum[i - 1];
  }
  long long answer = 0;
  int current_power = 0;
  int nn = n - 1;
  int kk = k;
  for (int i = n - 1; i >= 0; i--) {
    answer =
        (answer + bin_pow(10, current_power) * (s[i] - '0') * cnk(nn, kk)) %
        MOD;
    if (i > 0) {
      long long coef = cnk(nn - 1, kk - 1) * bin_pow(10, current_power) % MOD;
      answer = (answer + pref_sum[i - 1] * coef) % MOD;
    }
    current_power++;
    nn--;
  }
  cout << answer << endl;
  return 0;
}
