#include <stdio.h>
#include <math.h>
FILE *f;
int a[1000001];long long l,i,z,n,s,d,j,x;char c;
int main()
{f=fopen("next.in","r");fscanf(f,"%c",&c);
 while(c!='\n'){a[++n]=c-48;fscanf(f,"%c",&c);}
 fscanf(f,"%Ld",&d);fclose(f);
 for(i=1;i<=n;i++)
  x=(x*10+a[i])%d;
 x=(d-x)%d;i=n;
 while(x){s=(x+a[i])/10;a[i]=(x+a[i])%10;x=s;i--;}
 if(i==-1)j=0;else j=1;
 f=fopen("next.out","w");for(i=j;i<=n;i++)fprintf(f,"%d",a[i]);fclose(f);
 return 0;
}