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 PHP (5.6.30) (judge verdict: Accepted)

<?php

// 標準入力を一行ずつ配列に代入します
//$line = fgets(STDIN); // 標準入力からの入力値を変数に代入

while ($line = fgets(STDIN)) {
   $tmp[] = trim($line);
}

// 配列を展開
$i = 0;
foreach ($tmp as $value){
 //echo $value."\n";
 if($i==0){
     $line = $value;
 } else {
     $K = $value;
 }
 $i++;
}

$arr1 = str_split($line);

$i =1;
foreach ($arr1 as $value) {
    // code...
    //echo $value."\n";
    if($value<>1){
        echo $value;
        exit();
    }
    if ($i==$K){
        echo 1;
        exit();
    }
    
    $i++;
}
echo 1;

?>