<?php
    // Here your code !
    $n = trim(fgets(STDIN));
    $m = trim(fgets(STDIN));
    $x = "";
    if($n > 100000000000000){
        $n = $n / 1000;
        $x = "000";
    }
    
    echo floor(($n / $m) / 1000) * 1000;
    echo $x;
?>