Problem: Opposite to Grisha's nice behavior, Oleg, though he has an entire year at his disposal, didn't manage to learn how to solve number theory problems in the past year. That's why instead of Ded Moroz he was visited by his teammate Andrew, who solemnly presented him with a set of n distinct prime numbers alongside with a simple task: Oleg is to find the k-th smallest integer, such that all its prime divisors are in this set. 

Input

The first line contains a single integer n (1 ≤ n ≤ 16).

The next line lists n distinct prime numbers p1, p2, ..., pn (2 ≤ pi ≤ 100) in ascending order.

The last line gives a single integer k (1 ≤ k). It is guaranteed that the k-th smallest integer such that all its prime divisors are in this set does not exceed 1018.

Output

Print a single line featuring the k-th smallest integer. It's guaranteed that the answer doesn't exceed 1018.

Examples

Input

3
2 3 5
7


Output

8


Input

5
3 7 11 13 31
17


Output

93

Note

The list of numbers with all prime divisors inside {2, 3, 5} begins as follows:

(1, 2, 3, 4, 5, 6, 8, ...)

The seventh number in this list (1-indexed) is eight.

Solution (in JAVA):

Solution:
import java.io.*;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.*;

public class Mainn {

	public static class InputReader {
		public BufferedReader reader;
		public StringTokenizer tokenizer;

		public InputReader() {
			reader = new BufferedReader(new InputStreamReader(System.in), 32768);
			tokenizer = null;
		}

		public InputReader(InputStream stream) {
			reader = new BufferedReader(new InputStreamReader(System.in), 32768);
			tokenizer = null;
		}

		public String next() {
			while (tokenizer == null || !tokenizer.hasMoreTokens()) {
				try {
					tokenizer = new StringTokenizer(reader.readLine());
				} catch (IOException e) {
					throw new RuntimeException(e);
				}
			}
			return tokenizer.nextToken();
		}

		public char nextChar() {
			return next().charAt(0);
		}

		public int nextInt() {
			return Integer.parseInt(next());
		}

		public long nextLong() {
			return Long.parseLong(next());
		}

		public double nextDouble() {
			return Double.parseDouble(next());
		}

		public int[] nextIntArr(int n) {
			int[] arr = new int[n];
			for (int i = 0; i < n; i++) {
				arr[i] = this.nextInt();
			}
			return arr;
		}

		public Integer[] nextIntegerArr(int n) {
			Integer[] arr = new Integer[n];
			for (int i = 0; i < n; i++) {
				arr[i] = new Integer(this.nextInt());
			}
			return arr;
		}

		public int[][] next2DIntArr(int n, int m) {
			int[][] arr = new int[n][m];
			for (int i = 0; i < n; i++) {
				for (int j = 0; j < m; j++) {
					arr[i][j] = this.nextInt();
				}
			}
			return arr;
		}

		public int[] nextSortedIntArr(int n) {
			int[] arr = new int[n];
			for (int i = 0; i < n; i++) {
				arr[i] = this.nextInt();
			}
			Arrays.sort(arr);
			return arr;
		}

		public long[] nextLongArr(int n) {
			long[] arr = new long[n];
			for (int i = 0; i < n; i++) {
				arr[i] = this.nextLong();
			}
			return arr;
		}

		public char[] nextCharArr(int n) {
			char[] arr = new char[n];
			for (int i = 0; i < n; i++) {
				arr[i] = this.nextChar();
			}
			return arr;
		}
	}

	public static InputReader scn = new InputReader();
	public static PrintWriter out = new PrintWriter(System.out);

	public static void main(String[] args) {
		// InputStream inputStream = System.in; // Useful when taking input other than
		// console eg file handling // check ctor of inputReader
		// To print in file use this:- out = new PrintWriter("destination of file
		// including extension");

		int n = scn.nextInt();
		long[] a = new long[n - n / 2], b = new long[n / 2];

		for (int i = 0; i < n; i++) {
			int x = scn.nextInt();
			if (i % 2 == 0) {
				a[i / 2] = x;
			} else {
				b[i / 2] = x;
			}
		}

		long k = scn.nextLong();
		
		if(k == 1) {
			out.println(1);
			out.close();
			return;
		}
		
		ArrayList<Long> A = new ArrayList<>(), B = new ArrayList<>();

		func(A, a, 1, 0);
		func(B, b, 1, 0);

		long[] AA = new long[A.size()];
		long[] BB = new long[B.size()];
		
		for(int i = 0; i < A.size(); i++) {
			AA[i] = A.get(i);
		}

		for(int i = 0; i < B.size(); i++) {
			BB[i] = B.get(i);
		}
		
		AA = radixSort(AA);
		
		int i = 0, j = AA.length - 1;
		while(i < j) {
			AA[i] = AA[i] ^ AA[j];
			AA[j] = AA[i] ^ AA[j];
			AA[i] = AA[i] ^ AA[j];
			
			i++;
			j--;
		}
		
		BB = radixSort(BB);		
		
		long l = 1, r = (long) 1e18;

		while (l < r - 1) {
			long mid = (l + r) / 2;

			long rv = count(AA, BB, mid);

			if (rv < k) {
				l = mid;
			} else {
				r = mid;
			}
		}

		out.println(r);
		out.close();
	}

	public static void func(ArrayList<Long> list, long[] arr, long val, int si) {
		if(si == arr.length) {
			list.add(val);
			return;
		}
		
		func(list, arr, val, si + 1);
		
		while(val <= (long)(1e18) / arr[si]) {
			func(list, arr, val *= arr[si], si + 1);
		}
	}

	public static long count(long[] a, long[] b, long k) {
		int j = 0;
		long rv = 0;

		for(int i = 0; i < a.length; i++) {
			while(j < b.length && b[j] <= k / a[i]) {
				j++;
			}
			
			rv += j;
		}

		return rv;
	}
	
	public static long[] radixSort(long[] f){ return radixSort(f, f.length); }
	public static long[] radixSort(long[] f, int n)
	{
		long[] to = new long[n];
		{
			int[] b = new int[65537];
			for(int i = 0;i < n;i++)b[1+(int)(f[i]&0xffff)]++;
			for(int i = 1;i <= 65536;i++)b[i]+=b[i-1];
			for(int i = 0;i < n;i++)to[b[(int)(f[i]&0xffff)]++] = f[i];
			long[] d = f; f = to;to = d;
		}
		{
			int[] b = new int[65537];
			for(int i = 0;i < n;i++)b[1+(int)(f[i]>>>16&0xffff)]++;
			for(int i = 1;i <= 65536;i++)b[i]+=b[i-1];
			for(int i = 0;i < n;i++)to[b[(int)(f[i]>>>16&0xffff)]++] = f[i];
			long[] d = f; f = to;to = d;
		}
		{
			int[] b = new int[65537];
			for(int i = 0;i < n;i++)b[1+(int)(f[i]>>>32&0xffff)]++;
			for(int i = 1;i <= 65536;i++)b[i]+=b[i-1];
			for(int i = 0;i < n;i++)to[b[(int)(f[i]>>>32&0xffff)]++] = f[i];
			long[] d = f; f = to;to = d;
		}
		{
			int[] b = new int[65537];
			for(int i = 0;i < n;i++)b[1+(int)(f[i]>>>48&0xffff)]++;
			for(int i = 1;i <= 65536;i++)b[i]+=b[i-1];
			for(int i = 0;i < n;i++)to[b[(int)(f[i]>>>48&0xffff)]++] = f[i];
			long[] d = f; f = to;to = d;
		}
		return f;
	}
}