#include <bits/stdc++.h>
using namespace std;
template <class T>
inline bool chkmin(T &x, T y) {
  return y < x ? x = y, 1 : 0;
}
template <class T>
inline bool chkmax(T &x, T y) {
  return x < y ? x = y, 1 : 0;
}
inline long long Max(long long x, long long y) { return x > y ? x : y; }
inline long long Min(long long x, long long y) { return x < y ? x : y; }
int n, m;
char s[100002];
long long Pow[100002], fac[100002], inv[100002], f[100002];
long long dp[100002];
void Add(long long &x, long long y) {
  x += y;
  if (x >= 1000000007) x %= 1000000007;
}
void Init() {
  Pow[0] = 1;
  for (int i = (1), i_end_ = (100002); i < i_end_; i++)
    Pow[i] = Pow[i - 1] * 10 % 1000000007;
  fac[0] = fac[1] = 1;
  inv[0] = inv[1] = 1;
  f[0] = f[1] = 1;
  for (int i = (2), i_end_ = (100002); i < i_end_; i++)
    fac[i] = fac[i - 1] * i % 1000000007;
  for (int i = (2), i_end_ = (100002); i < i_end_; i++)
    inv[i] = (1000000007 - (1000000007 / i)) * inv[1000000007 % i] % 1000000007;
  for (int i = (2), i_end_ = (100002); i < i_end_; i++)
    inv[i] = inv[i] * inv[i - 1] % 1000000007;
}
long long C(int n, int m) {
  if (m < 0 || m > n) return 0;
  return fac[n] * inv[m] % 1000000007 * inv[n - m] % 1000000007;
}
int main() {
  Init();
  scanf("%d%d%s", &n, &m, s + 1);
  for (int i = (1), i_end_ = (n); i < i_end_; i++) {
    Add(dp[i], dp[i - 1]);
    Add(dp[i], Pow[i - 1] * C(n - i - 1, m - 1) % 1000000007);
  }
  long long ans = 0;
  for (int i = (1), i_end_ = (n); i <= i_end_; i++) {
    Add(ans, 1ll * (s[n - i + 1] - '0') * dp[i - 1] % 1000000007);
    Add(ans, 1ll * (s[n - i + 1] - '0') * Pow[i - 1] % 1000000007 *
                 C(n - i, m) % 1000000007);
  }
  printf("%I64d\n", ans);
  return 0;
}
