#include <algorithm>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <ctime>
#include <iostream>
#include <sstream>
#include <functional>
#include <map>
#include <string>
#include <cstring>
#include <vector>
#include <queue>
#include <stack>
#include <deque>
#include <set>
#include <list>
#include <numeric>
using namespace std;
const double PI = 3.14159265358979323846;
const double EPS = 1e-12;
typedef pair<int,int> P;
typedef long long ll;
typedef unsigned long long ull;

ll INF = 1e12;

int main(){
	ll d, a, b, c;
	cin>>d>>a>>b>>c;
	if(a>c) swap(a, c);
	ll res = INF;
	if(b > c && c > a) res = 0;
	if(b < a && c > a) res = 0;
	if(d==0){
		cout<<(res==INF?-1:res)<<endl;
		return 0;
	}
	cerr<<res<<endl;
	ll a2 = a, b2 = b, c2 = c;
	{ // b > max(a, c)
		ll t1 = 0, t2 = 0;
		if(a>=b){
			t1 = (a-b)/d+1;
			a -= d*t1;
			if(a<0) a = 0;
		}
		if(c>=b){
			t2 = (c-b)/d+1;
			c -= d*t2;
			if(c<0) c = 0;
			if(c==a){
				t2++;
				c -= d;
			}
			if(c<0) c = 0;
			if(a==c) t2 = INF;
		}
		res = min(res, t1+t2);
	}
	cerr<<res<<endl;
	a = a2; b = b2; c = c2;
	{ // b < min(a, c)
		ll t1 = 0, t2 = 0;
		if(a==c){
			t1++;
			a -= d;
		}
		if(a<=0) t1 = INF;
		if(a<=b){
			t2 = (b-a)/d+1;
			b -= d*t2;
		}
		if(b<0) b = 0;
		if(b==a){
			t2++;
			b -= d;
		}
		if(b<0) b = 0;
		if(a==b) t2 = INF;
		res = min(res, t1+t2);
	}
	cout<<(res==INF?-1:res)<<endl;
	return 0;
}