#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")

#include <algorithm>
#include <bitset>
#include <climits>
#include <cmath>
#include <cstring>
#include <deque>
#include <forward_list>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;
typedef long long ll;
typedef pair<int, int> P;
typedef bitset<16> BS;

const ll MOD = 1E+09 + 7;
const ll INF = 1E15;
const int MAX_N = 1E+05;

ll N, D;

ll gcd(ll a, ll b);

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    cin >> N >> D;

    ll d = gcd(N, D);

    /*
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < N; j++) {
            cout << "i = " << i << ", j = " << j << ", dp = " << dp[i][j] << "\n";
        }
    }
    */

    cout << N / d - 1 << "\n";

    return 0;
}

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