Indexed set template

indexed_set.cpp

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

#include <ext/pb_ds/assoc_container.hpp>

using namespace __gnu_pbds;
template <class T>
using indexed_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

int main() {
}