#include <iostream>
#include <fstream>
#include <cstring>
#include <string>
#include <climits>
#include <algorithm>
#include <cmath>
using namespace std;

ifstream fin ("next.in");
ofstream fout("next.out");
#define MAX 1000002
#define lli x long long int x
#define ui x unsigned x

long long int i,s,m,a1,t,j,l,d,k,ci;
char n[MAX];

unsigned int a[MAX],b[20],c[MAX];


void inm(unsigned int* al, unsigned int* bl, unsigned int* dl)
{
    int* ml=new int[MAX];
    ml[0]=al[0]+bl[0]-1;
    for(i=1;i<=al[0];i++)
    {
        for(j=1;j<=bl[0];j++)
        {
            ml[i-1+j]+=al[i]*bl[j];

        }
    }

    for(i=1;i<=ml[0];i++)
    {

        if(ml[i]>9)
        {
            ml[i+1]+=ml[i]/10;
            ml[i]%=10;
        }
    }
    if(ml[i])
        ml[0]++;
    for(i=0;i<=ml[0];i++)
    {
        dl[i]=ml[i];
    }
    delete ml;


}

void transforma(long long int sos, unsigned int* al)
{
    long long int k=0;

    while(sos)
    {
        al[++k]=sos%10;

        sos/=10;
    }


    al[0]=k;

}

void fshow(unsigned int *al)
{
    for(i=al[0];i>=1;i--)
    {
        fout<<al[i];
    }
}

void imp(unsigned int* al,long long int d, unsigned int* cl)
{
    long long int p=0;
    for(i=al[0];i>=1;i--)
    {
        al[i]+=p;
        p=al[i]%d;
        cl[i]=al[i]/d;

        p*=10;
    }
    for(i=al[0];cl[i]==0;i--);
    cl[0]=i;
}

void add1(unsigned int* cl)
{
    i=1;
    cl[i]++;
    while(cl[i]==10)
    {
        cl[i]=0;
        i++;
        cl[i]++;
    }
    if(cl[cl[0]+1])
        cl[0]++;
}

void minus1(unsigned int* al)
{
    a[1]--;
    i=1;
    while(al[i]<0)
    {
        al[i]+=10;
        i++;
        al[i]--;
    }
    if(al[al[0]]==0)
        al[0]--;
}

int main()
{

    fin>>n;
    a[0]=strlen(n);
    for(i=1;i<=a[0];i++)
    {
        a[i]=n[a[0]-i]-'0';
    }
    minus1(a);
    fin>>d;
    imp(a,d,c);
    add1(c);
    transforma(d,b);
    for(i=a[0];i>=0;i--)
        a[i]=0;

    inm(b,c,a);
    fshow(a);

    return 0;
}