#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:256000000")
using namespace std;
long long n, k;
long long fact[1000010];
long long obr_fact[1000010];
long long pw[100010];
long long d[100010];
long long f[100010];
long long binpow(long long a, long long p) {
  long long res = 1;
  while (p) {
    if (p & 1) res = ((res * a) % (1000000007LL));
    a = ((a * a) % (1000000007LL));
    p >>= 1;
  }
  return res;
}
long long comb(long long n, long long k) {
  if (k < 0 || k > n) return 0;
  return ((((fact[n] * obr_fact[k]) % (1000000007LL)) * obr_fact[n - k]) %
          (1000000007LL));
}
void precalc() {
  fact[0] = 1;
  obr_fact[0] = binpow(fact[0], 1000000007LL - 2);
  for (int i = 1; i < 1000010; i++) {
    fact[i] = ((fact[i - 1] * i) % (1000000007LL));
    obr_fact[i] = binpow(fact[i], 1000000007LL - 2);
  }
  pw[0] = 1;
  for (int i = 1; i < 100010; i++) {
    pw[i] = ((pw[i - 1] * 10LL) % (1000000007LL));
  }
  f[0] = 0;
  for (int i = 1; i < 100010; i++) {
    f[i] =
        ((((pw[i - 1] * comb(n - i - 1, k - 1)) % (1000000007LL)) + f[i - 1]) %
         (1000000007LL));
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  scanf("%I64d %I64d\n", &n, &k);
  char tc;
  for (int i = 0; i < n; i++) {
    scanf("%c", &tc);
    d[i] = tc - '0';
  }
  precalc();
  long long ans = 0;
  for (int i = 0; i < n; i++) {
    ans = ((ans + ((((d[i] * f[n - i - 1]) % (1000000007LL)) +
                    ((((d[i] * pw[n - i - 1]) % (1000000007LL)) * comb(i, k)) %
                     (1000000007LL))) %
                   (1000000007LL))) %
           (1000000007LL));
  }
  cout << ans;
  return 0;
}
