#include <iostream>
#include <string>
#include <vector>
#include <cassert>

using namespace std;

struct Node
{
  int times;
  long long size;
  string str;
  vector<Node*> children;

  Node(int times, const string& s)
    : times(times), size(times * s.size()), str(s) {
    if (size >= 100000000000000LL) size = 100000000000000LL;
    return;
  }

  Node(int times, const vector<Node*>& children)
    : times(times), size(0), str(), children(children) {
    // cout << times << "!" << endl;

    for (int i = 0; i < (int)children.size(); ++i) {
      size += children[i]->size * times;
      if (size >= 100000000000000LL) size = 100000000000000LL;
    }

    return;
  }

  ~Node() {
    for (int i = 0; i < (int)children.size(); ++i)
      delete children[i];

    return;
  }

  char search(int idx) {
    //    cout << idx << ", " << times << ", " << size << ", " << str << '\n';

    if (idx >= size) return '0';

    if (!str.empty())
      return str[idx % str.size()];

    int rest = idx % (size/times);
    //cout << "rest " << rest << endl;
    for (int i = 0; i < (int)children.size(); ++i) {
      if (children[i]->size > rest)
	return children[i]->search(rest);

      rest -= children[i]->size;
    }

    return '0';
  }
};

Node* parseTerm(const string& s, int& idx);

vector<Node*> parseExpr(const string& s, int& idx)
{
  vector<Node*> v;

  while (('0' <= s[idx] && s[idx] <= '9')
	 || ('A' <= s[idx] && s[idx] <= 'Z')) {
    v.push_back(parseTerm(s, idx));
  }

  return v;
}

Node* parseTerm(const string& s, int& idx)
{
  // cout << "parseTerm " << s << ", " << idx << endl;

  int times = 1;

  if ('0' <= s[idx] && s[idx] <= '9') {
    int n = 0;

    while ('0' <= s[idx] && s[idx] <= '9') {
      n *= 10;
      n += s[idx++] - '0';
    }

    times = n;
  }

  if (s[idx] == '(') {
    ++idx;
    vector<Node*> children = parseExpr(s, idx);
    assert(s[idx++] == ')');
    return new Node(times, children);
  }
  else {
    assert('A' <= s[idx] && s[idx] <= 'Z');

    string t;
    while ('A' <= s[idx] && s[idx] <= 'Z')
      t += string(1, s[idx++]);

    return new Node(times, t);
  }
}

int main()
{
  while (true) {
    string s;
    int idx;
    cin >> s >> idx;

    if (s == "0" && idx == 0) break;

    s += " ";

    int i = 0;
    vector<Node*> v = parseExpr(s, i);

    Node* root = new Node(1, v);

    cout << root->search(idx) << '\n';
  }

  return 0;
}