#include <bits/stdc++.h>
using namespace std;
int read() {
  int X = 0, w = 1;
  char c = getchar();
  while (c < '0' || c > '9') {
    if (c == '-') w = -1;
    c = getchar();
  }
  while (c >= '0' && c <= '9') X = X * 10 + c - '0', c = getchar();
  return X * w;
}
const int N = 100000 + 10;
const int mod = 1e9 + 7;
int qpow(int a, int b) {
  int c = 1;
  for (; b; b >>= 1, a = 1ll * a * a % mod)
    if (b & 1) c = 1ll * c * a % mod;
  return c;
}
int n, k;
char a[N];
int s[N], fac[N], ifac[N];
int C(int n, int m) { return 1ll * fac[n] * ifac[m] % mod * ifac[n - m] % mod; }
int main() {
  n = read(), k = read();
  scanf("%s", a + 1);
  for (int i = 1; i <= n; ++i) s[i] = s[i - 1] + a[i] - '0';
  fac[0] = 1;
  for (int i = 1; i <= n; ++i) fac[i] = 1ll * fac[i - 1] * i % mod;
  ifac[n] = qpow(fac[n], mod - 2);
  for (int i = n; i; --i) ifac[i - 1] = 1ll * ifac[i] * i % mod;
  int ans = 0;
  for (int i = 0; i <= min(n - 2, n - k + 1); ++i)
    ans = (ans + 1ll * qpow(10, i) * C(n - i - 2, k - 1) % mod * s[n - i - 1]) %
          mod;
  for (int i = k + 1; i <= n; ++i)
    ans =
        (ans + 1ll * qpow(10, n - i) * C(i - 1, k) % mod * (a[i] - '0')) % mod;
  printf("%d\n", ans);
  return 0;
}
