#include <bits/stdc++.h>
using namespace std;
const long long mod = 1e9 + 7;
const int N = 1e5 + 10;
int n, k;
char s[N];
int sumdigit;
long long fac[N], inv[N], facinv[N];
long long pow_mod(long long a, long long b, long long p) {
  long long t = 1;
  for (; b; b >>= 1, a = a * a % p)
    if (b & 1) t = t * a % p;
  return t;
}
long long C(long long n, long long k) {
  if (k < 0 || k > n || n < 0) return 0;
  if (k == 0 || k == n) return 1;
  return fac[n] * facinv[k] % mod * facinv[n - k] % mod;
}
int main() {
  fac[0] = 1;
  for (int i = 1; i <= 100000; i++) fac[i] = fac[i - 1] * i % mod;
  inv[1] = 1;
  for (int i = 2; i <= 100000; i++)
    inv[i] = (mod - mod / i) * inv[mod % i] % mod;
  facinv[0] = 1;
  for (int i = 1; i <= 100000; i++) facinv[i] = facinv[i - 1] * inv[i] % mod;
  cin >> n >> k;
  scanf("%s", s + 1);
  long long ans = 0;
  for (int i = n; i >= 1; i--) {
    ans += sumdigit * pow_mod(10, i - 1, mod) % mod * C(n - i - 1, k - 1) % mod;
    ans += (s[n - i + 1] - '0') * pow_mod(10, i - 1, mod) % mod * C(n - i, k) %
           mod;
    sumdigit = (sumdigit + s[n - i + 1] - '0') % mod;
    ans %= mod;
  }
  cout << ans << endl;
  return 0;
}
