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// Jedna instancja wypisuje maksymalny wzrost.

#include "message.h"
#include "teatr.h"
#pragma warning(disable:4786)
#pragma warning(disable:4996)
#include <ctime>
#include<list>
#include <numeric>
#include<bitset>
#include<iostream>
#include<cstdio>
#include<algorithm>
#include<vector>
#include<set>
#include<map>
#include<functional>
#include<string>
#include<cstring>
#include<cstdlib>
#include<queue>
#include<utility>
#include<fstream>
#include<sstream>
#include<cmath>
#include<stack>
#include<assert.h>
#include<unordered_map>
#include<unordered_set>

using namespace std;

#define MEM(a, b) memset(a, (b), sizeof(a))
#define CLR(a) memset(a, 0, sizeof(a))
#define MAX(a, b) ((a) > (b) ? (a) : (b))
#define MIN(a, b) ((a) < (b) ? (a) : (b))
#define ABS(X) ( (X) > 0 ? (X) : ( -(X) ) )
#define S(X) ( (X) * (X) )
#define SZ(V) (int )V.size()
#define FORN(i, n) for(int i = 0; i < n; i++)
#define FORAB(i, a, b) for(int i = a; i <= b; i++)
#define ALL(V) V.begin(), V.end()
#define IN(A, B, C)  ((B) <= (A) && (A) <= (C))
#define AIN(A, B, C) assert(IN(A, B, C))

//typedef int LL;
typedef long long int LL;
//typedef __int128 LL;
//typedef __int64 LL;

typedef pair<int, int> PII;
typedef pair<LL, LL> PLL;
typedef pair<long double, long double> PDD;
typedef vector<int> VI;
typedef vector<LL> VL;
typedef vector<PII > VP;
typedef vector<double> VD;
typedef vector<LL> VL;
typedef long double ld;

int my_node, total_node;
int n;
VP P;

#define MaxVal 1000005
int tree[1000066];

int read(int idx)
{
	int sum = 0;

	while (idx > 0)
	{
		sum += tree[idx];
		idx -= (idx & -idx);
	}

	return sum;
}

//add val to f[idx].
//MaxVal = Just max value of index
void update(int idx, int val)
{
	while (idx <= MaxVal)
	{
		tree[idx] += val;
		idx += (idx & -idx);
	}
}


PII SelectPair() {
	int now = my_node;
	for (int i = 0; i < SZ(P); i++) {
		for (int j = i; j < SZ(P); j++) {
			if (now == 0) return { i, j };
			now--;
		}
	}
	return { -1, -1 };
}

int main() {
	my_node = MyNodeId();
	total_node = NumberOfNodes();
	n = GetN();
	if (n < 1000) {
		if (my_node) return 0;
		VI V(n);
		for (int i = 0; i < n; i++) V[i] = GetElement(i);
		int ans = 0;
		for (int i = 0; i < n; i++) {
			for (int j = i + 1; j < n; j++) {
				ans += (V[i] > V[j]);
			}
		}
		printf("%d\n", ans);
		return 0;
	}

	int part = 1;
	if (total_node == 100) part = 13;
	else if (total_node == 10) part = 4;

	for (int i = 0; i < part; i++) {
		int len = (n + part - 1) / part;
		P.push_back({ i * len, (i + 1) * len - 1 });
		P.back().second = MIN(P.back().second, n - 1);
	}

	PII p = SelectPair();
	if (p.first == -1) {
		PutLL(0, 0);
		Send(0);
		return 0;
	}

	LL ans = 0;
	if (p.first == p.second) {
		// Single node.
		int x = p.first;
		for (int i = P[x].second; i >= P[x].first; i--) {
			int num = GetElement(i);
			ans += read(num - 1);
			update(num, 1);
		}

	}
	else {
		// Double node.
		int y = p.first;
		int x = p.second;
		for (int i = P[x].first; i <= P[x].second; i++) {
			int num = GetElement(i);
			update(num, 1);
		}
		for (int i = P[y].first; i <= P[y].second; i++) {
			int num = GetElement(i);
			ans += read(num - 1);
		}
	}

	PutLL(0, ans);
	Send(0);

	if (my_node) return 0;

	ans = 0;
	for (int i = 0; i < total_node; i++) {
		Receive(i);
		ans += GetLL(i);
	}
	printf("%lld\n", ans);
	return 0;
}