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 C (GCC 5.4.1) (judge verdict: Accepted)

typedef unsigned char C,*S;typedef int I;typedef long long J;typedef double F;typedef void V;typedef unsigned long long UJ;
#define R return
#define P(b,a...)   if(b)return(a);
#define N(n,a...)   {I i=0,_n=(n);while(i<_n){a;++i;}}
#define W(b...)     while((b))
#define $(b,a...)   if(b){a;}else           
#define C(i,a...)   case i:{a;}break;       
#define S(i,c,a...) switch(i){c default:a;} 

#define MN(a,b)    ({typeof(a)_a=(a);typeof(a)_b=(b);_a<_b?_a:_b;})
#define MX(a,b)    ({typeof(a)_a=(a);typeof(a)_b=(b);_a>_b?_a:_b;})

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define O printf
#define SC scanf
I main(){C s[250];J k,i; // freopen("input.txt","r",stdin);freopen("output.txt","w",stdout);
 SC("%s\n%lld",s,&k);k--;for(i=0;s[i]=='1';i++);O("%c\n",k<i?'1':s[i]);}