#include <bits/stdc++.h>
#define x first
#define y second
using namespace std;
using ll=long long;
using pii=pair<int,int>;
using vi=vector<int>;
using vl=vector<ll>;
#define pb push_back
#define all(a) begin(a),end(a)

const int N=300010,M=5010,MOD=1e9+7;
const char en='\n';
const ll LLINF=1ll<<60;

int n,ccn[N],cn[N],psc[N],divc,pcl[M][M];
ll s,m,h[N],cs,mian=LLINF,cdif,iter;
vl divs;
vector<vector<pii>> ddivs;

void rek(int mi,int cuin)
{
	//cout<<mi<<' '<<cuin<<' '<<divs[mi]<<' '<<divs[cuin]<<endl;
	++iter;
	if (cuin==0)
	{
		if (cs>s) return;
		mian=min(mian,cdif+abs((s-cs)-cn[0])+abs(ccn[mi]-cn[mi])+(psc[divc]-psc[mi+1]));
		return;
	}
	if (mi>cuin) return;
	int po=pcl[cuin][mi];
	ll cdo=0;
	if (mi>ddivs[cuin][po].y)
	{
		cdo+=psc[cuin]-psc[mi+1]+abs(cn[mi]-ccn[mi]);
		mi=cuin;
	}
	if (mi==cuin)
	{
		++ccn[mi];
		cs+=divs[mi];
		if (cs<=s)
		{
			mian=min(mian,cdo+cdif+abs((s-cs)-cn[0])+abs(ccn[mi]-cn[mi])+(psc[divc]-psc[mi+1]));
		}
		cs-=divs[mi];
		--ccn[mi];
		return;
	}
	if (mi==ddivs[cuin][po].x)
	{
		++ccn[mi];
		cs+=divs[mi];
		rek(mi,ddivs[cuin][po].y);
		cs-=divs[mi];
		--ccn[mi];
	}
	if (mi==ddivs[cuin][po].x) ++po;
	if (po<(int)ddivs[cuin].size())
	{
		cdif+=abs(cn[mi]-ccn[mi])+psc[ddivs[cuin][po].x]-psc[mi+1];
		rek(ddivs[cuin][po].x,cuin);
		cdif-=abs(cn[mi]-ccn[mi])+psc[ddivs[cuin][po].x]-psc[mi+1];
	}
}

int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cin>>n>>s>>m;
	for (int i=0;i<n;++i) cin>>h[i];
	sort(h,h+n);
	set<ll> sd;
	for (ll i=1;i*i<=m;++i) if (m%i==0) sd.insert(i),sd.insert(m/i);
	divs=vl(all(sd));
	divc=divs.size();
	assert(divc<M);
	ddivs.resize(divc);
	//cout<<"found "<<divc<<" divisors."<<endl;
	for (int i=0;i<divc;++i) for (int j=0;j<=i;++j) if (divs[i]%divs[j]==0)
	{
		//cout<<i<<' '<<j<<endl;
		pcl[i][j]=ddivs[i].size();
		ddivs[i].pb({j,lower_bound(all(divs),divs[i]/divs[j])-divs.begin()});
	} else pcl[i][j]=ddivs[i].size();
	ll dod=0;
	//cout<<"made ddivs"<<endl;
	for (int i=0;i<n;++i)
	{
		auto it=lower_bound(all(divs),h[i]);
		if (it==divs.end() || (*it)!=h[i]) ++dod;
		else ++cn[it-divs.begin()];
	}
	for (int i=0;i<divc;++i) psc[i+1]=psc[i]+cn[i];
	rek(1,divc-1);
	if (mian<LLINF) cout<<mian+dod<<en;
	else cout<<-1<<en;
	//cout<<iter<<" iterations."<<endl;
}