#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define llong long long

uint gcd(uint a, uint b) {
    if(a % b == 0) return b;
    return gcd(b, a % b);
}

int main() {
    uint n, d;
    cin >> n >> d;

    cout << n / gcd(max(n, d), min(n, d)) - 1 << endl;
}