Untitled

#include <iostream>
using namespace std;
int main()
{
	long long a;
	cin >> a;
	int b;
	cin >> b;
	for (b ; b >0; b -= 1)
	{
		if (a % 10 != 0 or a < 10){
			a = a - 1;
		}
		else{
			a = a / 10;
		}
	}
	cout << a;
	return 0;
}