Solve in Python:
Little girl Tanya is learning how to decrease a number by one, but she does it wrong with a number consisting of two or more digits. Tanya subtracts one from a number by the following algorithm:  if the last digit of the number is non-zero, she decreases the number by one;  if the last digit of the number is zero, she divides the number by 10 (i.e. removes the last digit). 

You are given an integer number $n$. Tanya 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 positive integer number.


-----Input-----

The first line of the input contains two integer numbers $n$ and $k$ ($2 \le n \le 10^9$, $1 \le k \le 50$) — the number from which Tanya will subtract and the number of subtractions correspondingly.


-----Output-----

Print one integer number — the result of the decreasing $n$ by one $k$ times.

It is guaranteed that the result will be positive integer number. 


-----Examples-----
Input
512 4

Output
50

Input
1000000000 9

Output
1



-----Note-----

The first example corresponds to the following sequence: $512 \rightarrow 511 \rightarrow 510 \rightarrow 51 \rightarrow 50$.
n,k = list(map(int,input().split()))
for i in range(k):
    if n%10 == 0: n//=10
    else: n -=1
print(n)