#include "bits/stdc++.h"

using namespace std;

template< class T > T gcd(T a, T b) { return (b != 0 ? gcd<T>(b, a % b) : a); }
template< class T > T lcm(T a, T b) { return (a / gcd<T>(a, b) * b); }

const int maxN = 1000; //range
long long isVisited[maxN / 64 + 200];
vector<int> primes;
void Sieve_of_Eratosthenes() {
	int limit = maxN + 100;
	for (long long i = 3; i <= sqrt(limit) ; i += 2) {
		if (!(isVisited[i / 64] & (1LL << (i % 64)))) {
			for (long long j = i * i; j <= limit; j += 2 * i) {
				isVisited[j / 64] |= (1LL << (j % 64));
			}
		}
	}
	primes.push_back(2);
	for (long long i = 3; i <= limit; i += 2) {
		if (!(isVisited[i / 64] & (1LL << (i % 64)))) {
			primes.push_back(i);
		}
	}
}

bool is_prime(int n) {
	if (n < 2) return false;
	if (n == 2) return true;
	if (n % 2 == 0) return false;
	if (!(isVisited[n / 64] & (1LL << (n % 64)))) return true;
	return false;
}

int pf_count(int n) {
	int cnt = 0;
	for (int p : primes) {
		if (p * p > n) break;
		if (n % p == 0) {
			++cnt;
			while (n % p == 0) n /= p;
		}
	}
	if (n > 1) ++cnt;
	return cnt;
}

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
typedef tree<long long, null_type, less_equal<long long>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;

int main() {
	//~ Sieve_of_Eratosthenes();
	//~ int n = 10;
	//bool f = is_prime(n);//returns true if n is prime and returns false if n is not a prime number
	//cout << pf_count(n) << '\n'; //how many primes present in prime factorization of n
	//os.order_of_key(n) => returns counts of elements less then n
	//os.find_by_order(n) => nth position value
	//~ ordered_set os;
	//~ os.insert(10);
	//~ os.insert(20);
	//~ os.insert(30);
	//~ cout << os.order_of_key(30) << '\n';
	//~ cout << *os.find_by_order(2) << '\n';
}