#include <bits/stdc++.h>
using namespace std;

typedef pair<int, int> pii;
typedef long long ll;
typedef vector<int> vi;

#define pb push_back
#define eb emplace_back
#define mp make_pair
#define fi first
#define se second
#define rep(i,n) rep2(i,0,n)
#define rep2(i,m,n) for(int i=m;i<(n);i++)
#define ALL(c) (c).begin(),(c).end()

int d;
int a, b, c, nb, nc;
ll res = LLONG_MAX;

int main() {
    cin >> d >> b >> a >> c;
    nb = b; nc = c;

    if (d == 0) {
	if ((a < b && a < c && b != c) || (a > b && a > c && b != c)) {
	    puts("0");
	} else {
	    puts("-1");
	}
	return 0;
    }

    if (a) {
	ll t = 0;
	if (b >= a) {
	    ll ad = (b - a) / d;
	    t += ad;
	    b -= d * ad;
	    if (b >= a) {
		++t;
		b = max(0, b - d);
	    }
	}

	if (c >= a) {
	    ll ad = (c - a) / d;
	    t += ad;
	    c -= d * ad;
	    if (c >= a) {
		++t;
		c = max(0, c - d);
	    }
	}

	if (b != 0 || c != 0) {
	    if (b != c) res = t;
	    else {
		res = t + 1;
	    }
	}
    }

    b = nb;
    c = nc;

    if (b > c) swap(b, c);

    ll t = 0;
    if (b == c) {
	t = 1;
	b = max(0, b - d);
    }

    if (b) {
	if (b <= a) {
	    ll ad = (a - b) / d;
	    t += ad;
	    a -= d * ad;
	    if (a >= b) {
		++t;
		a = max(0, a - d);
	    }
	}
	res = min(res, t);
    }

    if (res == LLONG_MAX) res = -1;
    cout << res << endl;
    
    return 0;
}