#include <iostream>
#include <fstream>
#include <algorithm>
#include <cmath>
#include <cstdio>
#define BASE 10

using namespace std;
ifstream f("next.in");
ofstream g("next.out");
typedef int Huge[20000000];
Huge P,B,P1;

string s;

unsigned long long d,k;


unsigned long long Mod(Huge A, unsigned long X)
/* Intoarce A%X */
{ int i;
  unsigned long R=0;

  for (i=A[0];i;i--)
    R=(10*R+A[i])%X;
  return R;
}

void Add(Huge A, Huge B)
/* A <- A+B */
{ int i,T=0;

  if (B[0]>A[0])
    { for (i=A[0]+1;i<=B[0];) A[i++]=0;
      A[0]=B[0];
    }
    else for (i=B[0]+1;i<=A[0];) B[i++]=0;
  for (i=1;i<=A[0];i++)
    { A[i]+=B[i]+T;
      T=A[i]/10;
      A[i]%=10;
    }
  if (T) A[++A[0]]=T;
}
void AtribValue(Huge H, unsigned long long X) {
  H[0] = 0;
  while (X) {
      ++H[0];
      H[H[0]] = X % BASE;
      X /= BASE;
  }
}
void afis(Huge A)
{
    for(int i=1; i<=A[0]; i++)
    g<<A[A[0]-i+1];
}

int main()
{
    f>>s;
    f>>d;
    for(int i=0; i<s.size(); i++)
        {
            P[s.size()-i]=s[i]-'0';
            P1[s.size()-i]=s[i]-'0';
        }
    P[0]=s.size();
    P1[0]=s.size();
    k=Mod(P,d);
    if(k==0)
    {
        afis(P1);
    }else
    {
        AtribValue(B,d-k);
        Add(P1,B);
        afis(P1);
    }
    return 0;
}