#include<bits/extc++.h>
using namespace std;
using namespace __gnu_pbds;
struct range {
int i, l, r;
bool operator<(const range &rhs) const {
return l < rhs.l;
}
};
using oset = tree<range, null_type, less<range>, rb_tree_tag, tree_order_statistics_node_update>;
const int maxn = 1<<18;
int n, c, x, l[maxn], r[maxn];
vector<int> g[maxn];
int tr[maxn];
int qry(int l, int r) {
int ans = 0;
for(l += n, r += n; l < r; l>>=1, r>>=1) {
if(l&1) ans = max(ans, tr[l++]);
if(r&1) ans = max(ans, tr[--r]);
}
return ans;
}
array<int, 2> dfs(int v) {
if(v < n) return {0, -v};
int good = qry(l[v], r[v]) < x;
array<int, 2> cur = {-1, 1<<30};
for(auto &i : g[v]) cur = max(cur, dfs(i));
cur[0] += good;
return cur;
}
int GetBestPosition(int N, int C, int X, int *a, int *s, int *e) {
n = N, c = C, x = X;
for(int i = 0; i < n-1; i++) {
int j = n+i;
for(;j;j>>=1) tr[j] = max(tr[j], a[i]);
}
oset b;
for(int i = 0; i < n; i++) l[i] = r[i] = i, b.insert(range{i, l[i], r[i]});
for(int i = 0; i < c; i++) {
int len = e[i] - s[i] + 1;
int nl, nr;
for(int j = 1; j <= len; j++) {
auto t = *b.find_by_order(s[i]);
if(j == 1) nl = t.l;
if(j == len) nr = t.r;
g[n+i].push_back(t.i);
b.erase(t);
}
l[n+i] = nl;
r[n+i] = nr;
b.insert(range{n+i, nl, nr});
//for(auto i : b) cout << i.l << " " << i.r << " | "; cout << '\n';
}
return -dfs(n+c-1)[1];
}
