#include<iostream>
#include<algorithm>
#include<vector>
using namespace std;
long d,H[3];
main()
{
	cin>>d>>H[0]>>H[1]>>H[2];
	if(d==0)
	{
		bool ok=false;
		if(H[0]!=H[1]&&H[1]!=H[2]&&H[2]!=H[0])ok=true;
		if(ok)
		{
			if(H[0]<H[1]&&H[2]<H[1]||H[0]>H[1]&&H[2]>H[1]);
			else ok=false;
		}
		cout<<(ok?0:-1)<<endl;
		return 0;
	}
	vector<int>id={0,1,2};
	long ans=-1;
	do{
		if(id[1]==1)continue;
		long h[3];
		h[id[0]]=H[0];
		h[id[1]]=H[1];
		h[id[2]]=H[2];
		long now=0;
		for(int i=0;i<2;i++)
		{
			if(h[i]>h[i+1])continue;
			long t=h[i+1]-(h[i]-1);
			long x=(t+d-1)/d;
			h[i+1]-=x*d;
			now+=x;
			if(h[i+1]<0)h[i+1]=0;
		}
		if(h[0]>h[1]&&h[1]>h[2])
		{
			if(ans<0)ans=now;
			else if(ans>now)ans=now;
		}
	}while(next_permutation(id.begin(),id.end()));
	cout<<ans<<endl;
}