#include <bits/stdc++.h>
using namespace std;
template <typename T>
inline bool smin(T &a, const T &b) {
  return b < a ? a = b, 1 : 0;
}
template <typename T>
inline bool smax(T &a, const T &b) {
  return a < b ? a = b, 1 : 0;
}
const long long N = 1e5 + 10, mod = (long long)1e9 + 7;
long long n, k, ps[N], f[N], inv[N], pw10[N];
string s;
long long pw(long long x, long long y) {
  x %= mod;
  long long ret = 1;
  for (; y; y >>= 1, (x *= x) %= mod)
    if (y & 1) (ret *= x) %= mod;
  return ret;
}
long long C(long long n, long long r) {
  if (r > n || r < 0 || n < 0) return 0;
  return ((f[n] * inv[r] % mod) * inv[n - r] % mod) % mod;
}
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cin >> n >> k >> s;
  ps[0] = s[0] - '0';
  for (long long i = 1; i < n; ++i) (ps[i] = ps[i - 1] + (s[i] - '0')) %= mod;
  f[0] = inv[0] = 1;
  for (long long i = 1; i < N; ++i) {
    (f[i] = f[i - 1] * i) %= mod;
    inv[i] = pw(f[i], mod - 2);
  }
  pw10[0] = 1;
  for (long long i = 1; i < N; ++i) (pw10[i] = pw10[i - 1] * 10) %= mod;
  long long res = 0;
  for (long long sz = 0; sz <= n - 2; ++sz) {
    long long add =
        pw10[sz] * C(n - sz - 2, k - 1) % mod * ps[n - sz - 2] % mod;
    (res += add) %= mod;
  }
  for (long long i = 0; i < n; ++i) {
    long long add = (s[i] - '0') * pw10[n - i - 1] % mod * C(i, k);
    (res += add) %= mod;
  }
  cout << res << '\n';
}
