#include <iostream>
#include <fstream>

using namespace std;

ifstream fin ( "inversmodular.in" );
ofstream fout ( "inversmodular.out" );

void euclid_extins( int a, int b, int& x, int& y, int& d ) {
	if ( b == 0 ) {
		d = a;
		x = 1;
		y = 0;
		return;
	}
	int xx, yy, q = a / b;
	euclid_extins( b, a % b, xx, yy, d );
	x = yy;
	y = xx - yy * q;
}

int cmmdc( int a, int b ) {
	if ( b == 0 )
		return a;
	return cmmdc( b, a % b );
}

int main() {
    int a, n, x, y, d;
    fin >> a >> n;
    d = cmmdc( a, n );
    euclid_extins( a, n, x, y, d );
    x %= n;
    if ( x < 0 ) {
        x += n;
    }
    fout << x << "\n";
    return 0;
}