#include <bits/stdc++.h>

using namespace std;

ifstream in("next.in");
ofstream out("next.out");

short n[1000100];
int sz, p;
long long D, mod;
string s;

int main(){
	in >> s;
	in >> mod;
	sz = s.size();
	n[0] = sz;
	for(int i = sz; i; i--)
		n[++p] = s[i - 1] - 48;
	for(int i = sz; i; i--)
		D = (10LL * D + (long long)n[i]) % mod;
	D = mod - D;
	int i;
	for(i = 1; i <= n[0] || D; i++, D /= 10)
		n[i] = (D += (long long)n[i]) % 10;
	n[0] = i - 1;
	for(i = n[0]; i; i--)
		out << n[i]; 
	return 0;
}