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#include <iostream>
#include <vector>

#include "message.h"
#include "teatr.h"

using namespace std;
typedef long long ll;

int* tmp;
const int lim = 1e6;

ll count_inv(int* a, int s, int t) {
	if (s+1 == t) return 0;

	if (s+2 == t) {
		if (a[s] > a[s+1]) {
			swap(a[s], a[s+1]);
			return 1;
		} else {
			return 0;
		}
	}

	int m = (s+t) / 2;

	ll inv = count_inv(a, s, m) + count_inv(a, m, t);

	for (int i = s; i < t; i++) {
		tmp[i] = a[i];
	}

	int it = s, l = s, r = m;

	while (l < m && r < t) {
		if (tmp[l] <= tmp[r]) {
			a[it++] = tmp[l++];
		} else {
			inv += m - l;
			a[it++] = tmp[r++];
		}
	}

	while (l < m) { a[it++] = tmp[l++]; }
	while (r < t) { a[it++] = tmp[r++]; }

	return inv;
}

int main() {
	ios_base::sync_with_stdio(0);

	int id = MyNodeId();
	int n = GetN();
	int num_nodes = NumberOfNodes();

	if (n < num_nodes) {
		if (id == 0) {
			num_nodes = 1;
		} else {
			return 0;
		}
	}

	int per_node = n / num_nodes;
	int s = per_node * id, t = per_node * (id + 1);
	s += min(id, n % num_nodes);
	t += min(id+1, n % num_nodes);

	int* a = new int[t - s];
	tmp = new int[t - s];
	for (int i = s; i < t; i++) {
		a[i - s] = GetElement(i);
	}

	ll local_inv = count_inv(a, 0, t - s);

	delete[] tmp;

	if (id > 0) {
		ll* p = new ll[lim]();

		for (int i = 0; i < s; i++) {
			p[GetElement(i)-1]++;
		}

		ll gt = 0, gte;

		for (int i = lim-1; i >= 0; i--) {
			gte = p[i] + gt;
			p[i] = gt;
			gt = gte;
		}

		for (int i = s; i < t; i++) {
			local_inv += p[a[i-s]-1];
		}

		delete[] p;
	}

	delete[] a;

	if (id == 0) {
		ll sum_inv = local_inv;
		for (int i = 1; i < num_nodes; i++) {
			int inst = Receive(-1);
			sum_inv += GetLL(inst);
		}

		cout << sum_inv << endl;
	} else {
		PutLL(0, local_inv);
		Send(0);
	}

	return 0;
}