# A Magic Lamp

Time Limit: 2000/1000 MS (Java/Others)

Memory Limit: 32768/32768 K (Java/Others)

## Description

Kiki likes traveling. One day she finds a magic lamp, unfortunately the genie in the lamp is not so kind. Kiki must answer a question, and then the genie will realize one of her dreams.
The question is: give you an integer, you are allowed to delete exactly m digits. The left digits will form a new integer. You should make it minimum.
You are not allowed to change the order of the digits. Now can you help Kiki to realize her dream?

## Input

There are several test cases.
Each test case will contain an integer you are given (which may at most contains 1000 digits.) and the integer m (if the integer contains n digits, m will not bigger then n). The given integer will not contain leading zero.

## Output

For each case, output the minimum result you can get in one line.
If the result contains leading zero, ignore it.

## Sample Input

178543 4
1000001 1
100001 2
12345 2
54321 2

## Sample Output

13
1
0
123
321

lcy

## Source

HDU 2009-11 Programming Contest