#include<stdio.h>

int main(void){

int a;
int b;
scanf("%d",&a);
scanf("%d",&b);
int c;
c=1;
int t=0;
int t2=0;
for(int i=0;i<b;i++)
        c=c*10;

t=a%c;
if(t>=(c/2))
         t2=((a/c)+1)*c ;   
             else
         t2=(a/c)*c;

if(b==0)t2=t2-1;         
printf("%d",t2);            
            
    
  
 return 0;   
}