#include <algorithm>
#include <cstdio>
#include <iostream>
#include <map>
#include <math.h>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <string.h>
#include <vector>
using namespace std;

#define ll long long
#define INF (1 << 30)
#define INFLL (1LL << 60)

#define FOR(i,a,b) for(ll i = (a);i<(b);i++)
#define REP(i,a) FOR(i,0,(a))
#define MP make_pair

int main() {
	ll n, d, ans = 0;
	cin >> n >> d;
	set<ll> used;
	ll now = 0;
	while(true){
		if(used.find(now) != used.end()) break;
		used.insert(now);

		if((n - now) % d == 0){
			ans += (n - now) / d;
			now += ((n - now) / d) * d;
		}else{
			ans += (n - now) / d + 1;
			now += ((n - now) / d + 1) * d;
		}

		now %= n;

		// cout << ":" << now << "-" << ans << endl;
	}

	cout << ans - 1 << endl;
	return 0;
}