Champernowne Constant

Time Limit : 8 sec, Memory Limit : 65536 KB

Problem C:Champernowne Constant

Champernown constant is an irrational number represented in decimal by "0." followed by concatenation of all positive integers in the increasing order. The first few digits of this constant are: 0.123456789101112...

Your task is to write a program that outputs the K digits of Chapnernown constant starting at the N-th place for given two natural numbers K and N.


The input has multiple lines. Each line has two positive integers N and K (N ≤ 109, K ≤ 100) separated by a space.

The end of input is indicated by a line with two zeros. This line should not be processed.


For each line, output a line that contains the K digits.

Sample Input

4 5
6 7
0 0

Output for the Sample Input


Source: ACM International Collegiate Programming Contest , ACM-ICPC Japan Alumni Group Practice Contest 2009, 2009-11-01