#include<stdio.h>
#include<string.h>
int n;
long long d;
char s[1<<20];
int v[1<<20];

int main()
{
    freopen("next.in","r",stdin);
    freopen("next.out","w",stdout);
    int i;
    long long r=0,t;
    gets(s+1);
    n=strlen(s+1);
    scanf("%lld",&d);
    for(i=1;i<=n;i++)
        v[n-i+1]=s[i]-'0';
    for(i=n;i>0;i--)
        r=(r*10+v[i])%d;
    t=(d-r)%d;
    for(i=1;i<=n || t;i++,t/=10)
        v[i]=(t+=v[i])%10;
    n=i-1;
    for(i=n;i>=1;i--)
        printf("%d",v[i]);
	return 0;
}