#include <bits/stdc++.h>
const long long mod = 998244353;
using namespace std;
pair<long long, long long> dp[20][2][1 << 10];
int k;
int s[20];
long long pw[20];
pair<long long, long long> solve(int i, bool U, int mask) {
  if (i < 0) return {0, 1};
  pair<long long, long long> &ret = dp[i][U][mask];
  if (ret.first + 1) return ret;
  ret = {0, 0};
  int L = U ? 9 : s[i];
  for (int e = 0; e <= L; e++) {
    int Mask = mask | (mask > 0 ? (1 << e) : ((e > 0) * (1 << e)));
    if (__builtin_popcount(Mask) > k) continue;
    pair<long long, long long> temp = solve(i - 1, U || e < s[i], Mask);
    ret.first += temp.first + temp.second * e % mod * pw[i] % mod;
    ret.first %= mod;
    ret.second += temp.second;
    ret.second %= mod;
  }
  return ret;
}
int main() {
  ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  pw[0] = 1;
  for (int i = 1; i <= 18; i++) pw[i] = pw[i - 1] * 10LL % mod;
  long long l, r;
  cin >> l >> r >> k;
  for (int i = 0; i < 18; i++) s[i] = r % 10, r /= 10;
  memset(dp, -1, sizeof dp);
  long long ans = solve(17, 0, 0).first;
  l--;
  for (int i = 0; i < 18; i++) s[i] = l % 10, l /= 10;
  memset(dp, -1, sizeof dp);
  cout << ((ans - solve(17, 0, 0).first) % mod + mod) % mod;
  return 0;
}
