#include <cstdio>
#include <iostream>
#include <cmath>
#include <ctime>

using namespace std;

int main (){
    int a, n, b=1;
    cin >> a >> n;
    for(int i=0; i<n; i++) b*=10;
    
    int x=a%b;
    
    if(x>=b/2){ a+=b-x; cout << a; }
    else { a-=x; cout << a; }
    
    cout << endl;

    return 0;
}