Description

Xiaoming is learning how to subtract $1$ from a number, but he makes mistakes when dealing with two-digit numbers and larger numbers. Xiaoming performs the following operations on a number:
If the last digit of a number is not $0$, he subtracts $1$ from the number.
If the last digit of a number is $0$, he divides the number by $10$.
You have an integer $n$. Xiaoming will perform $k$ operations. Your task is to find the result after performing $k$ operations on this integer.

Input Format

The first line of input contains two integers $n$ and $k$ ($2≤n≤10^9$, $1≤k≤50$).

Output Format

Output a single integer—the result after Xiaoming performs $k$ operations on the integer $n$.

Sample

512 4

50