#include <bits/stdc++.h>
using namespace std;
const int mod = 1000000007;
const int N = 100010;
char s[N];
int fac[N], inv[N], sum[N];
long long mpow(long long a, long long b) {
  long long ans = 1;
  while (b) {
    if (b & 1) ans = ans * a % mod;
    a = a * a % mod;
    b >>= 1;
  }
  return ans;
}
long long com(int n, int m) {
  if (n < m) return 0;
  return 1LL * fac[n] * inv[m] % mod * inv[n - m] % mod;
}
int main() {
  int n, m;
  scanf("%d%d", &n, &m);
  scanf("%s", s + 1);
  inv[0] = fac[0] = 1;
  for (int i = 1; i <= n; i++) {
    fac[i] = 1LL * fac[i - 1] * i % mod;
    inv[i] = mpow(fac[i], mod - 2);
    sum[i] = sum[i - 1] + s[i] - '0';
  }
  long long ans = 0;
  for (int i = 1, base = 1; i <= n - m; i++, base = 10LL * base % mod) {
    ans = (ans + com(n - i - 1, m - 1) * sum[n - i] % mod * base) % mod;
    ans = (ans + com(n - i, m) * (s[n - i + 1] - '0') % mod * base) % mod;
  }
  cout << ans << endl;
  return 0;
}
