#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;
using ll = long long;

int main () {
    string N;
    ll K;
    cin >> N >> K;

    reverse(N.begin(), N.end());

    // 累積積を用いて上の桁から決定できる。
    vector<ll> acc(N.size());
    acc[0] = 1;

    for (int i = 1; i < N.size(); i++) {
        acc[i] = acc[i - 1] * (N[i - 1] - '0' + 1);
    }

    ll cur = 0;
    string ans;
    for (int i = static_cast<int>(N.size() - 1); 0 <= i; i--) {
        int d = static_cast<int>((K - cur - 1) / acc[i]);
        ans.push_back('0' + d);
        cur += d * acc[i];
    }

    for (int i = 0; i < ans.size(); i++) if (ans[i] != '0') {
        ans = ans.substr(i);
        break;
    }

    int zero = 0;
    for (int i = 0; i < ans.size(); i++) if (ans[i] == '0') zero++;

    if (zero == ans.size()) ans = "0";

    cout << ans << "\n";
}