#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=(n)-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define pqueue(x) priority_queue<x,vector<x>,greater<x>>
#define all(x) (x).begin(),(x).end()
#define CST(x) cout<<fixed<<setprecision(x)
#define vtpl(x,y,z) vector<tuple<x,y,z>>
#define rev(x) reverse(x);
using ll=long long;
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
using pl=pair<ll,ll>;
using vpl=vector<pl>;
using vvpl=vector<vpl>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=1e9+10;
const ll INF=4e17;
const ll dy[9]={0,1,-1,0,1,1,-1,-1,0};
const ll dx[9]={1,0,0,-1,1,-1,1,-1,0};
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
bool isok(vl v){
    if(v[0]==v[1]||v[1]==v[2]||v[0]==v[2])return false;
    if(v[1]==max({v[0],v[1],v[2]})||v[1]==min({v[0],v[1],v[2]}))return true;
    return false;
}
int main(){
    ll d;cin >> d;
    vector<ll> v(3);rep(i,3)cin >> v[i];
    if(isok(v))cout << 0 << endl,exit(0);
    if(d==0)cout << -1 << endl,exit(0);
    ll ans=INF;
    ll ret=0;
    if(v[2]==v[0]){
        v[0]=max(v[0]-d,0LL);
        ret++;
        if(isok(v))cout << 1 << endl,exit(0);
    }
    ll mini=min({v[0],v[1],v[2]});
    if(mini){
        ll p=(v[1]-mini)/d+1;
        vl nv=v;nv[1]=max(0LL,v[1]-d*p);
        if(isok(nv)){
            chmin(ans,ret+p);
        }
    }
    if(v[0]>=v[1]){
        ll p=(v[0]-v[1])/d+1;
        v[0]=max(0LL,v[0]-p*d);
        ret+=p;
    }
    if(v[2]>=v[1]){
        ll p=(v[2]-v[1])/d+1;
        v[2]=max(0LL,v[2]-p*d);
        ret+=p;
    }
    if(v[0]==v[2]){
        v[0]=max(0LL,v[0]-d);
        ret++;
    }
    if(isok(v))chmin(ans,ret);
    if(ans==INF)cout << -1 << endl;
    else cout << ans << endl;



}