#include<iostream>
#include<cstdio>
#include<cmath>
#include<algorithm>
#include<cstring>
using namespace std;
int read()
{
	char ch;
	int x,f=1;
	while(ch=getchar(),!isdigit(ch))if(ch=='-')f=-1;
	x=ch-48;
	while(ch=getchar(),isdigit(ch))x=x*10+ch-48;
	return x*f;
}
inline 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,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;
}