Ayush is learning how to decrease a number by one, but he does it wrong with a number consisting of two or more digits. Ayush subtracts one from a number by the following algorithm:
if the last digit of the number is non-zero, he decreases the number by one.
if the last digit of the number is zero, he divides the number by 10.
You are given an integer number n
Ayush will subtract one from it k times. Your task is to print the result after all k subtractions.
It is guaranteed that the result will be a positive integer number.
Input
The first line of the input contains two integers n and k (2 ≤ n ≤ 10^9, 1 ≤ k ≤ 50) -- the number from which Ayush will subtract and the number of subtractions respectively.
Output
Print one integer number — the result of the decreasing n by one k times.
It is guaranteed that the result will be a positive integer number.
EXAMPLE
Sample Input 1
512 4
Sample Output 1
50
Sample Input 2
1000000000 9
Sample Output 2
1

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