Problem:
﻿Score: 300 points

Problem Statement

Mr. Infinity has a string S consisting of digits from 1 to 9. Each time the date changes, this string changes as follows:

Each occurrence of 2 in S is replaced with 22. Similarly, each 3 becomes 333, 4 becomes 4444, 5 becomes 55555, 6 becomes 666666, 7 becomes 7777777, 8 becomes 88888888 and 9 becomes 999999999. 1 remains as 1.

For example, if S is 1324, it becomes 1333224444 the next day, and it becomes 133333333322224444444444444444 the day after next.
You are interested in what the string looks like after 5 \times 10^{15} days. What is the K-th character from the left in the string after 5 \times 10^{15} days?

Constraints

S is a string of length between 1 and 100 (inclusive).

K is an integer between 1 and 10^{18} (inclusive).

The length of the string after 5 \times 10^{15} days is at least K.

Input

Input is given from Standard Input in the following format:

S
K

Output

Print the K-th character from the left in Mr. Infinity's string after 5 \times 10^{15} days.

Sample Input 1

1214
4

Sample Output 1

2

The string S changes as follows:

Now: 1214

After one day: 12214444

After two days: 1222214444444444444444

After three days: 12222222214444444444444444444444444444444444444444444444444444444444444444

The first five characters in the string after 5 \times 10^{15} days is 12222. As K=4, we should print the fourth character, 2.

Sample Input 2

3
157

Sample Output 2

3

The initial string is 3. The string after 5 \times 10^{15} days consists only of 3.

Sample Input 3

299792458
9460730472580800

Sample Output 3

2

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        try (Scanner sc = new Scanner(System.in)) {
            char[] s = sc.next().toCharArray();
            long k = sc.nextLong();

            int i = 0;
            for (; i < s.length; i++) {
                if (s[i] != '1') {
                    i++;
                    break;
                }
            }

            if (k > i) {
                System.out.println(s[i - 1]);
                return;
            }
            System.out.println(1);

            // int n = sc.nextInt();
            // int[] a = new int[201];
            //
            // for (int i = 1; i < 201; i++) {
            // for (int j = 1; j <= i; j++) {
            // for (int k = j; j * k <= i; k++) {
            // if (j * k == i) {
            // if (j == k) {
            // a[i]++;
            // } else {
            // a[i] += 2;
            // }
            // }
            // }
            // }
            // }
            //
            // int sum = 0;
            // for (int i = 1; i <= n; i += 2) {
            // if (a[i] == 8) sum++;
            // }
            //
            // System.out.println(sum);
        }
    }
}