977A Wrong Subtraction

A. Wrong Subtraction

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

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

Copy

512 4

output

Copy

50

input

Copy

1000000000 9

output

Copy

1

Note

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

题意：CF第一套div3，难度开始下降，1600分以上的做了不会算rating，第一次是测试的，注册的人很多，很多大佬都AK了，仰望.....输入一个数n，和k，对这个数进行k次操作，每次可以有两种操作方式，如果这个数的个数为0，就可以/10，相当于把0去掉，如果不为0，就减一。经过k次操作，输出当前n的值。

题解：模拟

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#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,k;
    cin>>n>>k;
    while(k--)
    {
        if(n%10==0)
            n/=10;
        else n--;
    }
    cout<<n;
    return 0;
}