#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:16777216")
using namespace std;
long long qpow(long long a, long long b) {
  long long res = 1, base = a;
  while (b) {
    if (b % 2) res = res * base;
    base = base * base;
    b /= 2;
  }
  return res;
}
long long powmod(long long a, long long b) {
  long long res = 1, base = a;
  while (b) {
    if (b % 2) res = res * base % 1000000007;
    base = base * base % 1000000007;
    b /= 2;
  }
  return res;
}
char s[100005];
long long f[100005];
long long g[100005];
int n, m;
void read() {
  scanf("%d%d", &n, &m);
  scanf("%s", s + 1);
  f[0] = 1;
  for (int i = 1; i <= n; i++) f[i] = f[i - 1] * i % 1000000007;
  g[n] = powmod(f[n], 1000000007 - 2);
  for (int i = n - 1; i >= 0; i--) g[i] = g[i + 1] * (i + 1) % 1000000007;
}
inline long long C(int k1, int k2) {
  if (k2 > k1) return 0;
  return f[k1] * g[k2] % 1000000007 * g[k1 - k2] % 1000000007;
}
void work() {
  long long ans = 0, sum = 0, mul = 1;
  for (int i = n; i >= 1; i--) {
    long long t = s[i] - '0';
    ans = (ans + (sum + mul * C(i - 1, m) % 1000000007) * t) % 1000000007;
    sum = (sum + C(i - 2, m - 1) * mul) % 1000000007;
    mul = mul * 10 % 1000000007;
  }
  printf("%I64d\n", ans);
}
int main() {
  read();
  work();
  return 0;
}
