#include <iostream>
#include <algorithm>
#include <vector>
#include <set>
#include <string>
#include <cstdlib>
using namespace std;

int type_digit = 0;
int type_char = 1;

const long long infinity = 1000 * 1000 + 10;
struct Expression{
  int type;
  int d;
  Expression * child;
  char c;
  Expression * successor;

  long long length() const {
    if(type == type_char){
      if(successor){
	  return min(infinity, successor->length() + 1);
      }
      return 1;
    }else{
      long long length = child->length() * d;
      if(length > infinity){return infinity;}
      if(successor){
	length += successor->length();
      }
      return min(infinity, length);
    }
  }
  char f(int i) const {
    //cout << "i = " << i << endl;
    //cout.flush();
    if(type == type_char){
      if(i == 0){return c;}
      if(successor){
	return successor->f(i - 1);
      }
    }else{
      long long length = child->length();
      if(length >= infinity){length = infinity;}
      if(length == infinity){
	return child->f(i);
      }
      length *= d;
      if(length > i){
	return child->f(i % child->length());
      }
      if(successor){
	return successor->f(i - length);
      }
    }
    return '0';
  }

};

Expression * expression(const char * & p){
  if(p[0] == '\0' or p[0] == ')'){
    return 0;
  }else if(isdigit(p[0])){
    int k = strtol(p, (char **)&p, 10);
    Expression *e = new Expression();
    if(p[0] == '('){
      p++;
      e->child = expression(p);
      p++;
    }else{
      e->child = new Expression();
      e->child->type = type_char;
      e->child->c = p[0];
      e->child->successor = 0;
      p++;
    }
    e->type = type_digit;
    e->d = k;
    e->successor = expression(p);
    return e;
  }else{
    Expression *e = new Expression();
    e->c = p[0];
    e->type = type_char;
    e->successor = expression(++p);
    return e;
  }
}


int main(){
  while(true){
    string s;
    int i;
    cin >> s >> i;
    if(s == "0" and i == 0){break;}
    
    const char *p = s.c_str();
    //cout << "p = " << p << endl;
    Expression * e = expression(p);
    //cout << "p = " << p << endl;
    //cout << "e = " << e << endl;

    cout << e->f(i) << endl;
    //cout << e->c << endl;

  }
}