#include <bits/stdc++.h>
using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");

int a, b, c, x, y, d, n;
int cmmdc(int a, int b, int &x, int &y)
{
    if(b == 0)
    {
        x = 1, y = 0;
        return a;
    }
    int x0, y0, d;
    d = cmmdc(b, a%b, x0, y0);

    x = y0;
    y = x0-(a/b)*y0;
    return d;
}

int main()
{
    fin >> a >> b;
    d = cmmdc(a, b, x, y);

    while(x < 0)
        x += b;
    fout << x;
    return 0;
}