#include <cstdio>
#include <cstring>
using namespace std;
const int maxDigits=1000000;
class HugeN{
	private:
		char x[maxDigits];
	public:
		HugeN();
		HugeN(long long k);
		void read();
		void print();
		long long operator % (long long k);
		HugeN operator + (HugeN &other);
};
HugeN::HugeN(){
	x[0]=0;
}
HugeN::HugeN(long long k){
	x[0]=0;
	do{
		x[(int)++x[0]]=k%10;
		k/=10;
	} while (k);
}
void HugeN::read(){
	x[0]=0;
	char c;
	while (scanf("%c",&c)!=EOF && c!='\n'){
		c=c-'0';
		x[(int)++x[0]]=c;
	}
	for (int i=1;i<=(x[0]>>1);i++){
		int aux;
		aux=x[i];
		x[i]=x[x[0]-i+1];
		x[x[0]-i+1]=aux;
	}
}
void HugeN::print(){
	for (int i=x[0];i>=1;i--){
		printf("%d",x[i]);
	}
}
long long HugeN::operator % (long long k){
	long long r=0;
	for (int i=x[0];i>=1;i--){
		r=(r*10+x[i])%k;
	}
	return r;
}
HugeN HugeN::operator + (HugeN &other){
	HugeN temp;
	temp.x[0]=(x[0] > other.x[0] ? x[0] : other.x[0]);
	int tr=0;
	for (int i=1;i<=temp.x[0];i++){
		tr=x[i]+other.x[i]+tr;
		temp.x[i]=tr%10;
		tr=tr/10;
	}
	if (tr){
		temp.x[(int)++temp.x[0]]=tr;
	}
	return temp;
}
int main(){
	freopen("next.in","r",stdin);
	freopen("next.out","w",stdout);
	long long k,r;
	HugeN n,t;
	n.read();
	scanf("%lld",&k);
	r=n%k;
	if (r==0){
		r=k;
	}
	r=k-r;
	HugeN ot(r);
	t=n+ot;
	t.print();
	return 0;
}