#include <fstream>
#include <cstring>
using namespace std;
ifstream cin("next.in");
ofstream cout("next.out");
const int MAX_DIGITS=1000003;
const int BASE=10;
class HUGE{
    private : int x[MAX_DIGITS];
    public :
        //constructori
        HUGE(){
        memset (x,0, sizeof(x));
            x[0]=1;
        }
        HUGE (const string s){
            memset(x,0,sizeof(x));
            x[0]=s.size();
            for (int j=s.size()-1,i=1;i<=x[0];++i,--j)
                x[i]=s[j]-'0';
        }
    HUGE(int n){
        memset(x,0,sizeof(x));
        x[0]=0;
        do{
            ++x[0];
            x[x[0]]=n%10;
            n/=10;
        }while (n);
    }
    HUGE(const HUGE &other){
    memcpy(x,other.x, sizeof(other.x));
    }
    int cmp (const HUGE &other){
    if (x[0]> other.x[0])
        return 1;
    if (x[0]<other.x[0])
        return -1;
    for (int i=x[0];i;--i){
        if (x[i]>other.x[i])
            return 1;
        if (x[i]<other.x[i])
            return -1;
    }
    return 0;
    }
    void print (){
    for (int i=x[0];i>0;--i)
        cout<<x[i];
        cout<<"\n";
    }
    HUGE  operator + (const HUGE &other);
    void operator += (const HUGE &other);
    HUGE  operator - (const HUGE &other);
    void  operator -=(const HUGE &other);
    HUGE operator + ( int n);
    void operator +=( int n);
    HUGE  operator * ( int n);
    HUGE  operator *(const HUGE &other);
    void operator *= (int n);
    HUGE  operator / ( int n);
    void operator /=( int n);
    long long  operator % ( long long n);
    void operator = (const HUGE &other);
};
void HUGE :: operator = (const HUGE &other){
memcpy(x,other.x, sizeof(other.x));
}
HUGE HUGE::operator + (const HUGE &other){
//c.x = x+ other.x
HUGE c;
int i,tr=0, aux;
c.x[0]=max(x[0],other.x[0]);
for (i=1;i<=c.x[0];i++){
    aux=x[i]+other.x[i]+tr;
    c.x[i]=aux%BASE;
    tr=aux/BASE;
}
if (tr){
    c.x[0]++;
    c.x[c.x[0]]=tr;

}
return c;
}
void  HUGE:: operator += (const HUGE&other){
    //x=x+other.x
    int i,tr, aux;
    x[0]=max(x[0], other.x[0]);
    for (i=1,tr=0;i<=x[0];++i)
    {
        aux=x[i]+other.x[i]+tr;
        x[i]=aux%BASE;
        tr=aux/BASE;
    }
    if (tr){
        x[0]++;
        x[x[0]]=tr;
    }
}
HUGE HUGE::operator - (const HUGE &other){
//c.x = x- other.x
HUGE c;
int i,imprumut=0, aux;
c.x[0]=max(x[0],other.x[0]);
for (i=1;i<=c.x[0];i++){
    aux=x[i]-other.x[i]-imprumut;
    c.x[i]=aux;
    if (c.x[i]<0){
        c.x[i]+=BASE;
        imprumut=1;
        }
    else imprumut=0;
}
while (c.x[c.x[0]]==0 and c.x[0]>1){
    c.x[0]--;
}
return c;
}
void HUGE::operator -=(const HUGE &other){
//x.x = x- other.x
int i,imprumut=0, aux;
x[0]=max(x[0],other.x[0]);
for (i=1;i<=x[0];i++){
    aux=x[i]-other.x[i]-imprumut;
    x[i]=aux;
    if (x[i]<0){
        x[i]+=BASE;
        imprumut=1;
        }
    else imprumut=0;
}
while (x[x[0]]==0 and x[0]>1){
    x[0]--;
}
}
HUGE HUGE :: operator * (int k ){
//c=x*k
HUGE c;
c.x[0]=x[0];
int i,tr=0,aux;
for (i=1;i<=c.x[0];++i)
    {
        aux=x[i]*k+tr;
        c.x[i]=aux%BASE;
        tr=aux/BASE;
    }
while (tr){
    c.x[0]++;
    c.x[c.x[0]]=tr%BASE;
    tr/=BASE;
}
return c;
}
void  HUGE :: operator *=(int k ){
//x*=k
int i,tr=0,aux;
for (i=1;i<=x[0];++i)
    {
        aux=x[i]*k+tr;
        x[i]=aux%BASE;
        tr=aux/BASE;
    }
while (tr){
    x[0]++;
    x[x[0]]=tr%BASE;
    tr/=BASE;
}
}
void  HUGE :: operator /=(int k){
int i, t = 0;
      for (i = x[0]; i > 0; i--, t%=k){
            t = t * 10 + x[i];
              x[i] = t / k;
              }
      for (; x[0] > 1 and !x[x[0]]; x[0]--);
}
long long  HUGE :: operator % ( long long  k) {
      int i, t = 0;
      for (i = x[0]; i > 0; i--)
              t = (t * 10 + x[i]) % k;
      return t;
}
string s;
int main(){
    cin>>s;
   HUGE a(s);
   long long d;
   cin>>d;
   long long r= (a%d);
   if (!r)
        a.print();
   else {
        r=d-r;
        HUGE aux(r);
        a+=aux;
        a.print();
   }
}