#include <bits/stdc++.h>
const long long mod = 998244353;
using namespace std;
template <class c>
struct rge {
  c b, e;
};
template <class c>
rge<c> range(c i, c j) {
  return rge<c>{i, j};
}
template <class c>
auto dud(c* x) -> decltype(cerr << *x, 0);
template <class c>
char dud(...);
struct debug {
  template <class c>
  debug& operator<<(const c&) {
    return *this;
  }
};
pair<long long, long long> dp[20][2][2][1 << 10][2];
int k;
bool vis[20][2][2][1 << 10][2];
int s1[20], s2[20];
long long pw[20];
pair<long long, long long> solve(int i, bool D, bool U, int mask, bool take) {
  if (i < 0) return {0, 1};
  pair<long long, long long>& ret = dp[i][D][U][mask][take];
  if (vis[i][D][U][mask][take]) return ret;
  vis[i][D][U][mask][take] = 1;
  ret = {0, 0};
  for (int e = 0; e < 10; e++) {
    if ((!D && e > s1[i]) || (!U && e < s2[i])) continue;
    int Mask = mask | ((take || (e > 0)) * (1 << e));
    if (__builtin_popcount(Mask) > k) continue;
    pair<long long, long long> temp =
        solve(i - 1, D || e < s1[i], U || e > s2[i], Mask, take || e > 0);
    ret.first += temp.first;
    ret.first %= mod;
    ret.second += temp.second;
    ret.second %= mod;
    ret.first += temp.second * e % mod * pw[i] % mod;
    ret.first %= 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++) s1[i] = r % 10, r /= 10, s2[i] = l % 10, l /= 10;
  cout << solve(17, 0, 0, 0, 0).first;
  return 0;
}
