#include <iostream>
#include <cstdio>
#include <string>
#include <iomanip>
#include <cmath>
#include <cstdlib>
#include <algorithm>
using namespace std;
void gcd(long long a,long long b,long long& x,long long& y)
{if(!b)
{x=1;y=0;return;}
else
{
	gcd(b,a%b,x,y);
	int m=x;
	x=y;
	y=m-((int)a/(int)b)*y;
}
}
int main()
{
	long long a,b;
	long long x,y;
	freopen("mod.in","r",stdin);
	freopen("mod.out","w",stdout);
	cin>>a>>b;
	gcd(a,b,x,y);
	while(x<=0)x+=b;
	cout<<x<<endl;
	return 0;
}