#include <bits/stdc++.h>
using namespace std;
int n;
vector<int> h;
const int INF = 1e9;
struct node {
int left = -1;
int right = -1;
};
vector<node> nodes;
vector< vector<int> > binary_lifting(262144 + 10, vector<int>(30, -1)); // It tells you the 2^j ancestor of i.
void init(int N, vector<int> H) {
n = N;
h = H;
nodes = vector<node>(n); // It's a graph, has the index to the children.
for (int i = 1; i < n; i++) {
int target = i - 1;
while (H[target] <= H[i]) {
if (target == -1) {
break;
}
target = nodes[target].left;
}
nodes[i].left = target;
}
for (int i = n - 2; i >= 0; i--) {
int target = i + 1;
while (H[target] <= H[i]) {
if (target == -1) {
break;
}
target = nodes[target].right;
}
nodes[i].right = target;
}
// Create the binary_lift
// Create the base ancestors;
for (int i = 0; i < n; i++) {
int greatest = -1;
int ancestor = -1;
if (nodes[i].left != -1 && greatest < H[nodes[i].left]) {
greatest = H[nodes[i].left];
ancestor = nodes[i].left;
}
if (nodes[i].right != -1 && greatest < H[nodes[i].right]) {
greatest = H[nodes[i].right];
ancestor = nodes[i].right;
}
binary_lifting[i][0] = ancestor;
}
for (int i = 1; i < 30; i++) {
for (int j = 0; j < n; j++) {
if (binary_lifting[j][i - 1] == -1) {
binary_lifting[j][i] = -1;
}
else {
binary_lifting[j][i] = binary_lifting[binary_lifting[j][i - 1]][i - 1];
}
}
}
return;
}
int find_ancestor(int source, int distance) {
int pos = source;
for (int i = 31; i >= 0; i--) {
if (distance & (1<<i)) {
pos = binary_lifting[pos][i];
if (pos == -1) {
return -1;
}
}
}
return pos;
}
int minimum_jumps(int A, int B, int C, int D) {
if (A != B || C != D) {
return -1;
}
// return next_jump(find_ancestor(3, 131072 - 1), 6);
int high = 262144;
int low = 0;
int ans = -1;
// Bin-search the amount of jumps.
while (low <= high) {
int mid = (low + high) / 2;
int target0 = find_ancestor(A, mid);
int target1 = find_ancestor(A, mid + 1);
// cout << "ANS: " << ans << '\n';
// cout << "TARGET: " << target << '\n';
if (h[target0] < h[C] && h[C] <= h[target1]) {
ans = mid;
}
if (target0 == -1 || h[C] <= h[target0]) {
high = mid - 1;
}
else {
low = mid + 1;
}
}
// cout << "Height: " << h[find_ancestor(A, ans)] << '\n';
// cout << "Position: " << find_ancestor(A, ans) << '\n';
// cout << "Jumps: " << ans << '\n';
if (nodes[find_ancestor(A, ans)].left == C || nodes[find_ancestor(A, ans)].right == C) {
return ans + 1;
}
else {
return -1;
}
}
