#include "jumps.h"
#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ff first
#define ss second
const int mod = 1e9 + 7;
const int inf = 1e9;
const int logn = 20;
template<typename T>
int len(T &a){return a.size();}
vector<vector<int>> up, low;
int n;
bool sub1 = 1;
vector<int> h; vector<int> pos;
struct SparseT{
vector<vector<int>> t;
int n, logn;
int join(int a, int b){
return max(a,b);
}
int neutral(){
return 0;
}
SparseT (){}
SparseT (int _n){
init(_n);
}
SparseT (vector<int> &a){
build(a);
}
void init(int _n){
n = _n;
logn = 32 - __builtin_clz(n);
t.assign(_n, vector<int>(logn, neutral()));
}
void build(vector<int> &a){
init((int)(a.size()));
for(int i = 0; i < n; i ++){
t[i][0] = a[i];
}
for(int i = 1; i < logn; i ++){
for(int j = 0; j + (1 << i) <= n; j ++){
t[j][i] = join(t[j][i - 1], t[j + (1 << (i - 1))][i - 1]);
}
}
}
int get(int l, int r){
if(l > r) return neutral();
int k = 31 - __builtin_clz(r - l + 1);
return join(t[l][k], t[r - (1 << k) + 1][k]);
}
} t;
void init(int N, vector<int> H) {
h = H;
n = N;
pos.resize(n);
for(int i = 0; i < n; i ++) h[i] --;
for(int i = 0; i < n; i ++) pos[h[i]] = i;
vector<int> st;
vector<int> lef(n), rig(n);
for(int i = 0; i < n; i ++){
if(h[i] != i + 1) sub1 = 0;
while(!st.empty() && st.back() <= h[i]) st.pop_back();
if(st.empty()) lef[i] = -1;
else lef[i] = st.back();
st.push_back(h[i]);
}
if(sub1) return;
st.clear();
for(int i = n - 1; i >= 0; i --){
while(!st.empty() && st.back() <= h[i]) st.pop_back();
if(st.empty()) rig[i] = -1;
else rig[i] = st.back();
st.push_back(h[i]);
}
up.assign(logn, vector<int> (n, -1));
low.assign(logn, vector<int> (n, -1));
for(int i = 0; i < n; i ++){
up[0][h[i]] = max(lef[i], rig[i]);
}
t.build(h);
// first max, then min
for(int j = 1; j < logn; j ++){
for(int i = 0; i < n; i ++){
if(up[j - 1][i] == -1) continue;
//cout << (up[j][i]) << endl;
up[j][i] = up[j - 1][up[j - 1][i]];
}
}
for(int i = 0; i < n; i ++){
if(lef[i] == -1 && rig[i] == -1) continue;
if(lef[i] == -1) low[0][h[i]] = rig[i];
else if(rig[i] == -1) low[0][h[i]] = rig[i];
else low[0][h[i]] = min(rig[i], lef[i]);
}
for(int j = 1; j < logn; j ++){
for(int i = 0; i < n; i ++){
if(low[j - 1][i] == -1) continue;
low[j][i] = low[j - 1][low[j - 1][i]];
}
}
}
int minimum_jumps(int A, int B, int L, int R) {
if(sub1) return L - B;
int obst = t.get(B, L - 1);
int mn = inf;
for(int C = L; C <= R; C ++){
if(h[C] <= obst) continue;
int l = A - 1, r = B;
while(r - l > 1){
int m = (l + r) / 2;
if(t.get(m, C - 1) < h[C]){
r = m;
}else l = m;
}
int st = t.get(r, B);
int ans = 0;
for(int j = logn - 1; j >= 0; j --){
if(up[j][st] != -1 && up[j][st] <= h[C]){
st = up[j][st];
ans += 1 << j;
}
}
for(int j = logn - 1; j >= 0; j --){
if(low[j][st] != -1 && low[j][st] <= h[C]){
ans += 1 << j;
st = low[j][st];
}
}
mn = min(mn, ans);
}
return (mn == inf ? -1 : mn);
}
