// http://infoarena.ro/problema/next
#include <stdio.h>
#include <string.h>

FILE *fin = fopen("next.in","r"), *fout = fopen("next.out","w");
char N[1000000];
int REZ[1000000];
long long D, S;

long mod(char a[],long long b)
{
 long i;
 long long t = 0;
 for(i = S - 2 ; i >= 0; i--)
	{
	 t = (t * 10 + (a[i] - '0')) % b;
	}
 return t;
}

void suma(long long b)
{
 int i, t = 0;
 for (i = 0; b || t; i++, b /= 10, t /= 10)
	REZ[S - i - 2] = (t += ((N[S - i - 2] - '0') + b % 10)) %  10;
}

int main()
{
 long long r;
 fgets(N, 1000000, fin);
 S = strlen(N);
 fscanf(fin, "%lld\n", &D);
 r = mod(N, D);
// r2 = (D - r1) % D;
 suma(r);
 for (long i = 0; i < S - 1; i++)
	fprintf(fout, "%d", REZ[i]);
 fcloseall();
 return 0;
}