#include <bits/stdc++.h>

using namespace std;

namespace {

    typedef double real;
    typedef long long ll;

    template<class T> ostream& operator<<(ostream& os, const vector<T>& vs) {
        if (vs.empty()) return os << "[]";
        os << "[" << vs[0];
        for (int i = 1; i < vs.size(); i++) os << " " << vs[i];
        return os << "]";
    }
    template<class T> istream& operator>>(istream& is, vector<T>& vs) {
        for (auto it = vs.begin(); it != vs.end(); it++) is >> *it;
        return is;
    }

    ll d;
    ll h[3];
    void input() {
        cin >> d;
        for (int i = 0; i < 3; i++) cin >> h[i];
    }

    const ll INF = 1LL<<50;

    ll calc() {
        ll p = 0;
        if (h[0] == h[2]) {
            p++;
            h[0] = max(0LL, h[0] - d);
            if (h[0] == h[2]) {
                return INF;
            }
        }
        if (h[0] > h[2]) swap(h[0], h[2]);

        ll lb = min(h[0], h[2]);
        ll ub = max(h[0], h[2]); 
        if (h[1] > ub) return p;
        if (h[1] < lb) return p;

        assert(h[0] <= h[1] && h[1] <= h[2]);
        ll ans = INF;
        // 逵溘ｓ荳ｭ荳九￡
        ll x = ((h[1] - lb + 1) + d - 1) / d;
        if (lb != max(0LL, h[1] - d * x)) {
            ans = min(ans, x);
        }

        // 蜿ｳ荳九￡
        ll y = ((h[2] - h[1] + 1) + d - 1) / d;
        if (h[1] != max(0LL, h[2] - d * y)) {
            ans = min(ans, y);
            if (h[0] == h[2]) p++;
        }

        return ans + p;
    }

    void solve() {
        ll a = calc();
        cout << (a >= INF ? -1 : a) << endl;
    }
}

int main() {
    input(); solve();
    return 0;
}