#include<stdio.h>
 
void gcd(int a, int b, int &x, int &y){
	int xn, yn;
	if (b == 0){
		x = 1;
		y = 0;
		return;
	}
	gcd(b, a % b, xn, yn);
	x = yn;
	y = xn - (a / b) * yn;    
}

int main(){
	int a ,b, x, y;

	freopen("inversmodular.in","r",stdin);
	freopen("inversmodular.out","w",stdout);

	scanf("%d %d ",&a, &b);
   
	gcd(a, b, x, y);

	while(x<=0)
		x+=b;

	printf("%d", x);
	
	return 0;
}