#include <bits/stdc++.h>
#include "jumps.h"
#define FIXED_FLOAT(x) std::fixed <<std::setprecision(20) << (x)
#define all(v) (v).begin(), (v).end()
using namespace std;
#define forn(i,n) for (int i = 0; i < (n); ++i)
#define rforn(i, n) for(int i = (n) - 1;i >= 0;--i)
#define sz(x) (int)x.size()
#define ff first
#define se second
#define mp make_pair
using ll = long long;
int mod = (ll)1e9 + 7;
const int INF = 1e9 + 1;
const double eps = 1e-7;
template <class T> using V = vector<T>;
template <class T> using VV = V<V<T>>;
template<class T, size_t SZ> using AR = array<T, SZ>;
template<class T> using PR = pair<T, T>;
template <typename XPAX>
bool ckma(XPAX &x, XPAX y) {
return (x < y ? x = y, 1 : 0);
}
template <typename XPAX>
bool ckmi(XPAX &x, XPAX y) {
return (x > y ? x = y, 1 : 0);
}
V<int> g[200001];
int dis[200001];
const int L = 19;
int pl[200001];
int pr[200001];
int F[200001][L];
int W[200001][L];
int H[200001];
bool firstcase = 1;
int n;
V<int> S[200001 * 4];
void build(V<int> &a, int v, int tl, int tr) {
if (tl == tr) {
S[v] = {a[tl]};
} else {
int tm = (tl + tr) / 2;
build(a, v*2, tl, tm);
build(a, v*2+1, tm+1, tr);
merge(S[v*2].begin(), S[v*2].end(), S[v*2+1].begin(), S[v*2+1].end(),
back_inserter(S[v]));
}
}
int query(int v, int tl, int tr, int l, int r, int x) {
if (l > r)
return -1;
if (l == tl && r == tr) {
vector<int>::iterator pos = lower_bound(S[v].begin(), S[v].end(), x);
if(pos != S[v].begin()) {
pos--;
return *pos;
}
return -1;
}
int tm = (tl + tr) / 2;
return max(query(v*2, tl, tm, l, min(r, tm), x),
query(v*2+1, tm+1, tr, max(l, tm+1), r, x));
}
void init(int N, V<int> a) {
for(auto &c : a)--c;
forn(i, N) H[i] = a[i];
n = N;
build(a, 1, 0, N-1);
H[N] = N;
stack<int> st;
forn(i, N) {
while(sz(st) && H[st.top()] < H[i])
st.pop();
if(sz(st))g[i].push_back(st.top());
pl[H[i]] = sz(st) ? H[st.top()] : N;
st.push(i);
}
while(sz(st))st.pop();
rforn(i, N) {
while(sz(st) && H[st.top()] < H[i])
st.pop();
if(sz(st))g[i].push_back(st.top());
pr[H[i]] = sz(st) ? H[st.top()] : N;
st.push(i);
}
forn(i, N) {
dis[i] = -1;
firstcase &= (H[i] == i);
}
pl[N] = pr[N] = N;
for(int i = 0;i <= N;++i) {
F[i][0] = max(pl[i], pr[i]);
W[i][0] = pr[i];
}
for(int j = 1;j < L;++j) {
forn(i,N+1) {
F[i][j] = F[F[i][j-1]][j-1];
W[i][j] = W[W[i][j-1]][j-1];
}
}
}
int minimum_jumps(int A, int B, int C, int D) {
if(firstcase)
return C-B;
if(A == B && C == D) {
int ret =0 ;
int f = H[A];
int t = H[C];
rforn(i, L) if(F[f][i] <= t) f = F[f][i], ret += 1 << i;
rforn(i, L) if(W[f][i] <= t) f = W[f][i], ret += 1 << i;
if(f != t)return -1;
return ret;
}
if(C == D) {
int t = H[C];
int f = query(1, 0, n-1, A, B, t);
if(f == -1)return -1;
int ret = 0;
rforn(i, L) if(F[f][i] <= t) f = F[f][i], ret += 1 << i;
rforn(i, L) if(W[f][i] <= t) f = W[f][i], ret += 1 << i;
if(f != t)return -1;
return ret;
}
queue<int> q;
V<int> clr;
auto reset = [&]() {
for(auto x : clr)
dis[x] = -1;
};
for(int a = A;a <= B;++a) {
q.push(a);
dis[a] = 0;
clr.push_back(a);
}
while(sz(q)) {
int v = q.front();
q.pop();
if(C <= v && v <= D) {
int rr = dis[v];
reset();
return rr;
}
for(auto c : g[v]) {
if(dis[c] == -1) {
dis[c] = dis[v]+1;
q.push(c);
clr.push_back(c);
}
}
}
reset();
return -1;
}
/*
int main() {
init(7, {3, 2, 1, 6, 4, 5, 7});
cout << minimum_jumps(3, 4, 6, 6) << '\n';
}
*/
