#include "jumps.h"
#include <vector>
using namespace std;
const int N = 200000;
typedef vector<int> vi;
int max(int a, int b) { return a > b ? a : b; }
int ll[N], rr[N], qu[N], n, special;
int dd[N], pp[N], pp_[N], dd_[N], qq[N], qq_[N];
void dfs(int *dd, int *pp, int *pp_, int i) {
if (dd[i])
return;
if (pp[i] == -1)
dd[i] = 1, pp_[i] = -1;
else {
int p, p_;
dfs(dd, pp, pp_, pp[i]);
p = pp[i], p_ = pp_[p];
dd[i] = dd[p] + 1, pp_[i] = dd[p] - dd[pp_[p]] != dd[p_] - dd[pp_[p_]] ? p : pp_[p_];
}
}
void init(int n_, vi aa) {
int i, cnt;
n = n_;
special = 1;
for (i = 0; i < n; i++)
if (aa[i] != i + 1) {
special = 0;
break;
}
cnt = 0;
for (i = 0; i < n; i++) {
while (cnt && aa[qu[cnt - 1]] < aa[i])
cnt--;
ll[i] = cnt == 0 ? -1 : qu[cnt - 1];
qu[cnt++] = i;
}
cnt = 0;
for (i = n - 1; i >= 0; i--) {
while (cnt && aa[qu[cnt - 1]] < aa[i])
cnt--;
rr[i] = cnt == 0 ? -1 : qu[cnt - 1];
qu[cnt++] = i;
}
for (i = 0; i < n; i++) {
pp[i] = ll[i] == -1 || rr[i] == -1 ? (ll[i] == -1 ? rr[i] : ll[i]) : (aa[ll[i]] < aa[rr[i]] ? ll[i] : rr[i]);
qq[i] = ll[i] == -1 || rr[i] == -1 ? (ll[i] == -1 ? rr[i] : ll[i]) : (aa[ll[i]] > aa[rr[i]] ? ll[i] : rr[i]);
}
for (i = 0; i < n; i++)
dfs(dd, pp, pp_, i), dfs(dd_, qq, qq_, i);
}
int query(int i, int j) {
int cnt = 0;
while (1)
if (qq_[i] != -1 && dd[qq_[i]] >= dd[j])
cnt += dd_[i] - dd_[qq_[i]], i = qq_[i];
else if (qq[i] != -1 && dd[qq[i]] >= dd[j])
cnt++, i = qq[i];
else
break;
while (1)
if (pp_[i] != -1 && dd[pp_[i]] >= dd[j])
cnt += dd[i] - dd[pp_[i]], i = pp_[i];
else if (pp[i] != -1 && dd[pp[i]] >= dd[j])
cnt++, i = pp[i];
else
break;
return i == j ? cnt : -1;
}
int dd1[N];
int minimum_jumps(int i1, int j1, int i2, int j2) {
if (special)
return i2 - j1;
else if (i1 == j1 && i2 == j2)
return query(i1, i2);
else {
int head, cnt, i;
for (i = 0; i < n; i++)
dd1[i] = n;
head = cnt = 0;
for (i = i1; i <= j1; i++)
dd1[i] = 0, qu[head + cnt++] = i;
while (cnt) {
int d;
i = qu[cnt--, head++], d = dd1[i] + 1;
if (i2 <= i && i <= j2)
return dd1[i];
if (ll[i] != -1 && dd1[ll[i]] > d)
dd1[ll[i]] = d, qu[head + cnt++] = ll[i];
if (rr[i] != -1 && dd1[rr[i]] > d)
dd1[rr[i]] = d, qu[head + cnt++] = rr[i];
}
return -1;
}
}
