#include <atcoder/all>
#include <bits/stdc++.h>
#define rep(i, a, b) for (ll i = (ll)(a); i < (ll)(b); i++)
using namespace atcoder;
using namespace std;

typedef long long ll;

template <typename T> ostream &operator<<(ostream &os, const vector<T> &v) {
    int n = v.size();
    rep(i, 0, n) { os << v[i] << " \n"[i == n - 1]; }
    return os;
}

int main() {
    string s;
    ll k;
    cin >> s >> k;
    k--;
    int n = s.size();
    vector<ll> v(n + 1, 1);
    reverse(s.begin(), s.end());
    rep(i, 0, n) { v[i + 1] = v[i] * (s[i] - '0' + 1); }
    string ans;
    ll nw = k;
    reverse(v.begin(), v.end());
    rep(i, 0, n) {
        ans += '0' + nw / v[i + 1];
        nw %= v[i + 1];
    }
    cout << stoll(ans) << endl;
}