UVA - 10427 - Naughty Sleepy Boys

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.LinkedList;

public class Main {

    public static void main(String[] args) throws IOException {
        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        StringBuffer sb = new StringBuffer("");
        String m = "";
        int []digits=new int[9];
        for(int i=1,temp=9;i<9;i++,temp*=10){
            digits[i]=digits[i-1]+temp*i;
        }
        while ((m = br.readLine()) != null) {
            int x = Integer.parseInt(m);
            if(x==-1)
                break;
            int index=0;
            for(int i=1;i<9;i++){
                if(digits[i]>=x){
                    index=i-1;
                    break;
                }
            }
            int temp=x-digits[index]-1;
            int indAns=temp/(index+1);
            int rem=temp%(index+1);
            int start=(int) Math.pow(10, index);
            String solution=start+indAns+"";
            sb.append(solution.charAt(rem)).append("\n");
           
        }
        System.out.print(sb);
    }


}