Wrong Subtraction

1000ms

262144K

Description:

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.

Sample Input:

512 4

Sample Output:

Sample Input:

1000000000 9

Sample Output:

Note:

The first example corresponds to the following sequence: $$$512 \rightarrow 511 \rightarrow 510 \rightarrow 51 \rightarrow 50$$$.

Informação

Provedor Codeforces

Código CF977A