#include<iostream>
#include<fstream>
#include<sstream>
#include<string>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<ctime>
#include<stack>
#include<queue>
#include<set>
#include<map>
#include<vector>
#include<list>
#include<algorithm>
#include<utility>
#include<complex>
#include<functional>
using namespace std;


#define input_init stringstream ss; string strtoken, token; istringstream is
#define input_line  getline(cin, strtoken);is.str(strtoken);is.clear(istringstream::goodbit)
#define input_token(num) ss.str(""); ss.clear(stringstream::goodbit); getline(is, token, ','); ss << token; ss >> num

typedef long long LL;

LL bsearch(LL a,LL b,LL d){
	if (b > a)return 0;
	LL high = (LL)1e9;
	LL low = (LL)0;
	while (high - low > 1){
		LL c = (high + low) / 2;
		if (b > a - c*d)high = c;
		else low = c;
	}
	return high;
}
LL res =-1;
int main(void){
	LL d,h1,h2,h3,h1_,h2_,h3_;
	cin >> d >> h1 >> h2 >> h3;
	if (h1 > h3)swap(h1, h3);
	if (d == 0){
		if ((h3 > h1&&h1 > h2) || (h2 > h3&&h3 > h1)){
			cout << 0 << endl;
		}
		else cout << -1 << endl;
		return 0;
	}

	LL c1,c2,c3;
	//h3>h1>h2
	c1 = bsearch(h1, h3, d);
	h1_ = max(h1 - d*c1, 0ll);
	c2 = bsearch(h2, h1_, d);
	h2_ = max(h2 - d*c2, 0ll);
	c3 = 0;
	h3_ = h3;
	if (h1_ != h2_)res = c1 + c2 + c3;

	//h2>h3>h1
	c3 = bsearch(h3, h2, d);
	h3_ = max(h3 - d*c3, 0ll);
	c1 = bsearch(h1, h3_, d);
	h1_ = max(h1 - d*c1, 0ll);
	c2 = 0;
	h2_ = h2;
	if (h1_ != h3_&&res==-1)res = c1 + c2 + c3;
	else if (h1_ != h3_)res = min(res, c1 + c2 + c3);
	cout << res << endl;
	return(0);
}