#include <bits/stdc++.h>
using namespace std;
const long long mod = 1e9 + 7;
int n, k;
char str[100005];
long long fac[100005], sum[100005];
long long modpow(long long a, long long b) {
  a %= mod;
  long long res = 1;
  while (b) {
    if (b & 1) res = res * a % mod;
    a = a * a % mod;
    b >>= 1;
  }
  return res;
}
long long C(long long a, long long b) {
  if (a < 0 || b < 0) return 0;
  if (b > a) return 0;
  return fac[a] * modpow(fac[b] * fac[a - b] % mod, mod - 2) % mod;
}
void init() {
  fac[0] = 1;
  for (int i = 1; i <= 100000; ++i) fac[i] = fac[i - 1] * i % mod;
}
int main() {
  init();
  scanf("%d%d", &n, &k);
  scanf("%s", str);
  long long p = 1;
  for (int i = n - 1; i >= 1; --i) {
    sum[i] = (sum[i + 1] + C(i - 1, k - 1) * p % mod) % mod;
    p = p * 10 % mod;
  }
  p = 1;
  for (int i = n; i >= k + 1; --i) {
    sum[i] = (sum[i] + C(i - 1, k) * p % mod) % mod;
    p = p * 10 % mod;
  }
  long long ans = 0;
  for (int i = 1; i <= n; ++i)
    ans = (ans + (long long)(str[i - 1] - '0') * sum[i] % mod) % mod;
  printf("%lld\n", ans);
}
