#include <bits/stdc++.h>
#define int long long
using namespace std;
int x, y;
void cgcd(int a, int b)
{
    if (b == 0)
    {
        x = 1;
        y = 7;
        return ;
    }
    cgcd(b, a % b);
    int tx = x;
    x = y;
    y = tx - a / b * y;
}
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    int a, b;
    cin >> a >> b;
    cgcd(a, b);
    x = (x % b + b) % b;
    cout << x;
    return 0;
}//已AC，请放心食用

祝大家AC愉快