#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using Pi = pair<int, int>;
using Pl = pair<ll, ll>;
using vint = vector<int>;
using vvint = vector<vint>;
using vvvint = vector<vvint>;
using vdouble = vector<double>;
using vvdouble = vector<vdouble>;
using vvvdouble = vector<vvdouble>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using uint = unsigned int;
using ull = unsigned long long;

template<typename T> using uset = unordered_set<T>;
template<typename T1, typename T2> using umap = unordered_map<T1, T2>;

constexpr int INF = (1 << 30) - 1;
constexpr ll LLINF = 1LL << 60;
constexpr int dy[] = {1, 0, -1, 0, 1, -1, -1, 1};
constexpr int dx[] = {0, 1, 0, -1, 1, 1, -1, -1};
constexpr char el = '\n';
constexpr int mod = 1000000007;
constexpr int mod2 = 998244353;
template<typename T> T gcd(T a, T b) { return (b ? gcd(b, a % b) : a); }
template<typename T> T lcm(T a, T b) { return (a / gcd(a, b) * b); }
template<typename T1, typename T2>
inline bool chmin(T1 &a, T2 b) { return (a > b && (a = b, true)); }
template<typename T1, typename T2>
inline bool chmax(T1 &a, T2 b) { return (a < b && (a = b, true)); }
template<typename T>
bool isin(T y, T x, T h, T w) { return (0 <= y && 0 <= x && y < h && x < w); }
template<typename T>
bool isin1(T y, T x, T h, T w) { return (0 < y && 0 < x && y <= h && x <= w); }

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

template<typename T>
istream& operator >>(istream &is, vector<T> &v) {
	for (auto &u : v) is >> u;
	return (is);
}

template<typename T1, typename T2>
istream& operator >>(istream &is, pair<T1, T2> &p) {
	return (is >> p.first >> p.second);
}

void expr(string &S, int &i);

string T;
int N;

int number(string &S, int &i) {
	int val = 0;
	while (isdigit(S[i])) {
		val *= 10;
		val += S[i]-'0';
		i++;
	}
	return (val);
}

string String(string &S, int &i) {
	string s;
	while (T.size() <= N && i < S.size() && isupper(S[i])) {
		s += S[i];
		T += S[i];
		i++;
	}
	return (s);
}

void par(string &S, int &i) {
	int val = number(S, i);
	//cout << "number : " << val << endl;
	string s;
	if (S[i] == '(') {
		int plen = T.size();
		i++;	
		expr(S, i);
		if (T.size() > N) return;
		//cout << val << " : " << plen << " " << T.size() << endl;
		for (int j = plen; j < T.size(); j++) {
			s += T[j];
		}
		i++;
	} else {
		s += String(S, i);
	}
	val--;
	for (int j = 0; j < val; j++) {
		T += s;
		if (T.size() > N) return;
	}
}

void expr(string &S, int &i) {
	while (i < S.size() && isupper(S[i]) || isdigit(S[i])) {
		if (isupper(S[i])) {
			String(S, i);
			//cout << i << " " << S.size() << " " << T.size() << endl;
			if (T.size() > N) return;
		} else {
			par(S, i);
			if (T.size() > N) return;
		}
	}
	return;
}

bool solve() {
	string S; cin >> S >> N;
	if (S == "0" && N == 0) return (false);
	T = "";
	int i = 0;
	expr(S, i);
	//cout << T.size() << endl;
	if (T.size() <= N) {
		cout << 0 << endl;
	} else {
		cout << T[N] << endl;
	}
	return (true);
}

void Main() {
	while (solve());
}

int main() {
	cin.tie(0);
	ios::sync_with_stdio(0);
	cout << fixed << setprecision(20);
	Main();
	return (0);
}



Measured memory_bytes: 6328