#include <fstream>
#include <algorithm>

using namespace std;
int i,b[20],a[1000005],nr,m;
long long d,t;
char x;
ifstream f("next.in");
ofstream g("next.out");
void scad()
{
    while(d>0)
    {
        b[++m]=d%10;
        d=d/10;
    }
    t=0;
    for(i=1;i<=nr || (t>0 || i<=m);i++)
    {
        t=t+a[i]+b[i];
        a[i]=t%10;
        t=t/10;
    }
    if(i>nr)nr=i-1;
    for(i=nr;i>=1;i--)
    {
        g<<a[i];
    }
}
int main()
{
    f.get(x);
    while(x!='\n')
    {
        x=x-'0';
        a[++nr]=x;
        f.get(x);
    }
    f>>d;
    reverse(a+1,a+nr+1);
    t=0;
    i=nr;
    while(i>=1)
    {
        t=t*10+a[i];
        t=t%d;
        i--;
    }
    if(t>0)
    {
        d=d-t;
        scad();
    }
    else
    {
        for(i=nr;i>=1;i--)
        {
            g<<a[i];
        }
    }
    return 0;
}