#include<stdio.h>
#include<string.h>
#define N 250000
char n[N],d[N];
int an[N],dn[N];
void creare(char s[N],int v[N])
{
	int n,i,k=0;
	n=strlen(s);
	k=0;
	v[k++]=n;
	for(i=0;i<n;i++)
		v[k++]=s[i]-'0';
}
void afis(int v[N])
{
	int i;
	if(v[v[0]]==0)
		printf("%d",0);
	else
		for(i=v[0];i>=1;i--)
			printf("%d",v[i]);
	printf("\n");
}
void suma(int v1[N],int v2[N],int sum[N])
{
	int i,t=0,k=1;
	for(i=1;i<=v1[0]&&i<=v2[0];i++)
	{
		sum[k++]=(v1[i]+v2[i]+t)%10;
		t=(v1[i]+v2[i]+t)/10;
	}
	while(i<=v1[0])
	{
		sum[k++]=(v1[i]+t)%10;
		t=(v1[i]+t)/10;
		i++;
	}
	while(i<=v2[0])
	{
		sum[k++]=(v2[i]+t)%10;
		t=(v2[i]+t)/10;
		i++;
	}
	if(t)
		sum[k++]=t;
	sum[0]=k-1;
}
void scad(int v1[N],int v2[N],int dif[N])
{
	int i,k=1,j;
	//inters(v1,v2);
	for(i=1;i<=v1[0]&&i<=v2[0];i++)
		if(v1[i]-v2[i]>=0)
		{
			dif[k++]=v1[i]-v2[i];
			if(v1[i]-v2[i]==0&&i==v1[0])
			{
			//	v1[0]--;
				//k--;
			}
		}
		else
		{
			dif[k++]=v1[i]+10-v2[i];
			for(j=i+1;v1[j]==0&&j<=v1[0];j++)
				v1[j]=9;
			v1[j]--;
			if(v1[j]==0&&j==v1[0])
				v1[0]--;
		}
	while(i<=v1[0])
	{
		dif[k++]=v1[i];
		i++;
	}
	dif[0]=k-1;
}
void div(int A[N], int B)  
{  
    int i, t = 0;  
    for (i = A[0]; i > 0; i--, t %= B)  
            A[i] = (t = t * 10 + A[i]) / B;  
    for (; A[0] > 1 && !A[A[0]]; A[0]--);  
}
int mod(int A[], int B)  
{  
    int i, t = 0;  
    for (i = A[0]; i > 0; i--)  
            t = (t * 10 + A[i]) % B;  
    return t;  
}
void inv(char s[N])
{
	int i,j;
	char aux;
	for(i=0,j=strlen(s)-1;i<j;i++,j--)
	{
		aux=s[i];
		s[i]=s[j];
		s[j]=aux;
	}
}
int main()
{
	freopen("next.in","r",stdin);
	freopen("next.out","w",stdout);
	int rest,d1,r2,v1[N],k=1,sum[N];
	scanf("%s%d",&n,&d1);
	inv(n);
	creare(n,an);
	//creare(d,dn);
	rest=mod(an,d1);
	r2=(d1-rest)%d1;
	while(r2)
	{
		v1[k++]=r2%10;
		r2/=10;
	}
	v1[0]=k-1;
	suma(an,v1,sum);
	afis(sum);
	return 0;
}