#include<bits/stdc++.h>
using namespace std;
#define ll int
#define pll pair<ll,ll>
#define ff first
#define ss second
#define endl "\n"
#define pb push_back
#define F(i,a,b) for(ll i=a;i<=b;i++)
const ll maxn=3e5+10 ;
const ll base=1e9;
const ll mod= 1e9+7 ;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
/// have medal in APIO
/// goal 2/8
ll nxtr[maxn][20];
ll nxtl[maxn][20];
ll nxtmx[maxn][20];
ll mxnxtmx[maxn][20];
ll b[maxn];
ll pos[maxn];
void init(ll n,vector<ll> a)
{
stack<ll> st;
for (int t=0;t<20;t++) nxtr[n+1][t]=n+1;
for (int i=n;i>=1;i--)
{
pos[a[i-1]]=i;
while (st.size()&&a[st.top()-1]<a[i-1]) st.pop();
if (st.size()) nxtr[i][0]=st.top();
else nxtr[i][0]=n+1;
for (int t=1;t<20;t++) nxtr[i][t]=nxtr[nxtr[i][t-1]][t-1];
st.push(i);
}
while (st.size()) st.pop();
for (int i=1;i<=n;i++)
{
while (st.size()&&a[st.top()-1]<a[i-1]) st.pop();
if (st.size()) nxtl[i][0]=st.top();
else nxtl[i][0]=0;
for (int t=1;t<20;t++) nxtl[i][t]=nxtl[nxtl[i][t-1]][t-1];
st.push(i);
}
for (int i=n;i>=1;i--)
{
pll nw=make_pair(0,pos[i]);
ll id=pos[i];
if (nxtl[id][0]!=0)
{
nw=max(nw,make_pair(a[nxtl[id][0]-1],nxtl[id][0]));
}
if (nxtr[id][0]!=n+1)
{
nw=max(nw,make_pair(a[nxtr[id][0]-1],nxtr[id][0]));
}
nxtmx[id][0]=nw.ss;
mxnxtmx[id][0]=max(id,nw.ss);
for (int t=1;t<20;t++) nxtmx[id][t]=nxtmx[nxtmx[id][t-1]][t-1],mxnxtmx[id][t]=max(mxnxtmx[id][t-1],mxnxtmx[nxtmx[id][t-1]][t-1]);
}
}
ll minimum_jumps(ll a,ll b,ll c,ll d)
{
a++;
b++;
c++;
d++;
ll nw=b;
for (int t=19;t>=0;t--)
{
if (nxtr[nxtl[nw][t]][0]<=d&&nxtl[nw][t]>=a)
{
nw=nxtl[nw][t];
}
}
if (nxtr[nw][0]>d) return -1;
ll ans=0;
for (int t=19;t>=0;t--)
{
ll h=nxtmx[nw][t];
if (nxtr[h][0]<=d&&mxnxtmx[nw][t]<c)
{
ans+=(1ll<<t);
nw=h;
}
}
// cout <<nw<<" "<<nxtr[nw][0]<<" "<<ans<<endl;
for (int t=19;t>=0;t--)
{
if (nxtr[nw][t]<c)
{
// cout <<nw<<" "<<t<<" wtf"<<" "<<nxtr[nw][t]<<endl;
nw=nxtr[nw][t];
ans+=(1ll<<t);
}
}
ans++;
nw=nxtr[nw][0];
// cout <<nw<<" "<<nxtr[nw][0]<<" "<<nxtmx[nw][0]<<" "<<nxtr[nw][0]<<endl;
if (nw<=d)
{
return ans;
}
else
{
return -1;
}
}
/*int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
if (fopen("t.inp","r"))
{
freopen("test.inp","r",stdin);
freopen("test.out","w",stdout);
}
ll n;
cin>> n;
vector<ll> vt;
for (int i=1;i<=n;i++)
{
ll x;
cin>> x;
vt.pb(x);
}
init(n,vt);
ll a,b, c, d;
cin>> a>> b>> c>> d;
a--;
b--;
c--;
d--;
cout <<minimum_jumps(a,b,c,d)<<endl;
}*/
