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 nn. Tanya will subtract one from it kk times. Your task is to print the result after all kk subtractions.

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

Input

The first line of the input contains two integer numbers nn and kk (2n1092≤n≤109, 1k501≤k≤50) — the number from which Tanya will subtract and the number of subtractions correspondingly.

Output

Print one integer number — the result of the decreasing nn by one kk 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: 5125115105150512→511→510→51→50.

#include<iostream>
#include<string.h>
using namespace std;
int main()
{
    int k;
    char a[20];
    while(cin>>a>>k)
    {
        int len=strlen(a);
        int j=0;
        for(int i=0;i<k;i++)
        {
            if(a[len-1-j]=='0')
                {
                    a[len-1-j]='*';
                    j++;
                }
            else
                a[len-1-j]=a[len-1-j]-1;
        }
       
        for(int i=0;i<len;i++)
        {
            if(a[i]!='*')
                cout<<a[i];
        }
        cout<<endl;

    }
    return 0;
}

 

posted @ 2018-09-24 16:49  知道了呀~  阅读(355)  评论(0编辑  收藏  举报