#include <iostream>
#include <cmath>
using namespace std;
int main()
{
 
 int c,k,z,br=0;
 cin>>c>>k;
 int niz[11];
 niz[0]=1;
 for(int x=1; x<10; x++)
 {
  niz[x]=niz[x-1]*10;        
 }
 int k1=niz[k];
 int pola=k1/2;
 int nest;

int uk=c/k1;
uk*=k1;
nest=c-uk;
if(nest>=pola){cout<<uk+k1<<endl;}
else{cout<<uk<<endl;}


  
return 0;}