#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 11;
const int mod = 1e9 + 7;
char s[N];
int sum[N];
long long p[N];
long long fac[N];
long long fac_ni[N];
pair<long long, long long> extend_gcd(long long a, long long b) {
  if (b == 0) return make_pair(1, 0);
  pair<long long, long long> t = extend_gcd(b, a % b);
  long long x = t.second;
  long long y = t.first - a / b * x;
  return make_pair(x, y);
}
long long ni(long long a, long long m) {
  return (extend_gcd(a, m).first % m + m) % m;
}
long long C(long long n, long long m) {
  if (n < m || m < 0) return 0;
  return ((fac[n] * fac_ni[m]) % mod * fac_ni[n - m]) % mod;
}
void init() {
  fac[0] = 1;
  fac_ni[0] = ni(fac[0], mod);
  p[0] = 1;
  for (int i = 1; i < N; i++) {
    fac[i] = fac[i - 1] * i;
    fac[i] %= mod;
    fac_ni[i] = ni(fac[i], mod);
    p[i] = p[i - 1] * 10;
    p[i] %= mod;
  }
}
int main() {
  init();
  int n, k;
  while (2 == scanf("%d%d", &n, &k)) {
    scanf("%s", s);
    long long ans = 0;
    sum[0] = 0;
    for (int i = 0; i < n; i++) {
      sum[i + 1] = sum[i] + s[i] - '0';
      ans *= 10;
      ans += s[i] - '0';
      ans %= mod;
    }
    if (k == 0) {
      cout << ans << endl;
      continue;
    }
    ans = 0;
    for (int i = 0; i < n; i++) {
      ans += sum[n - i - 1] * (p[i] * C(n - i - 2, k - 1) % mod);
      ans %= mod;
      ans += (s[n - i - 1] - '0') * (p[i] * C(n - i - 1, k) % mod);
      ans %= mod;
    }
    cout << ans << endl;
  }
  return 0;
}
