#include <cstdio>
#include <iostream>

using namespace std ;

int c, k, br, min_abs = 2000000000, sol, nesto ;
int num [] = { 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000 } ;

int abs ( int number ) {
    return max ( number, -number ) ;
}

int main ( void ) {
    cin >> c >> k ;
    for ( int i = 1 ; i < 10 ; ++i )
        if ( k == i ) br = num [ i-1 ] ;
    nesto = c % br;
    if ( nesto > br / 2 - 1 ) {
        cout << c + ( br - nesto ) ;
    }
    else {
        cout << c - nesto ;
    }
    return 0 ;
}