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#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <vector>
#include <set>
#include <map>
#include <cmath>
#include <ctime>
#include <queue>
#include <stack>
#include <bitset>
#include <cassert>
#include "message.h"
#include "teatr.h"
using namespace std;
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef long long ll;
typedef short int sint;
#define FOR(x, b, e) for(int x=(b); x<=(e); ++x)
#define FORD(x, b, e) for(int x=((int)(b))-1; x>=(e); --x)
#define REP(x, n) for(int x=0; x<(n); ++x)
#define ALL(c) c.begin(),c.end()
#define SIZE(x) ((int)((x).size()))
#define PB push_back
#define ST first
#define ND second
#define mp(x,y) make_pair(x,y)
#define DEBUG 1
#define debug(x) {if (DEBUG)cerr <<#x <<" = " <<x <<endl; }
#define debugv(x) {if (DEBUG) {cerr <<#x <<" = "; FOREACH(it, (x)) cerr <<*it <<", "; cout <<endl; }}
#define REMAX(a,b) (a)=max((a),(b));
#define REMIN(a,b) (a)=min((a),(b));
#define wez(n) int (n); scanf("%d",&(n));
#define wez2(n,m) int (n),(m); scanf("%d %d",&(n),&(m));

// int GetN() { return 100 * 1000 * 1000; }
// int GetElement(int i) { 
// if (i < 100 * 1000 * 1000 - 3) return 1 + i / 100;
// else return 100 * 1000 * 1000 - i;
// }
// int GetN() { return 5;}
// int GetElement(int i) {
// 	int a[]={5, 2, 4, 4, 3};
// }

const int GR = 1000000; // 3;
const int MAXVAL = 1000000;
int a[GR], pom[GR];
int bucketCnt[MAXVAL + 1];
ll inw_cnt;

void mergeSort(int p, int q) {
	// cout << "merge sort: " << p << ' ' << q << endl;
	if (p + 1 == q || p == q) {
		return;
	}
	int s = (p + q) / 2;
	mergeSort(p, s);
	mergeSort(s, q);
	int wsk1 = p, wsk2 = s, ind = p;
	while (wsk1 < s && wsk2 < q) {
		if (a[wsk1] <= a[wsk2]) {
			pom[ind++] = a[wsk1++];
		} else {
			inw_cnt += s - wsk1;
			pom[ind++] = a[wsk2++];
		}
	}
	while (wsk1 < s) {
		pom[ind++] = a[wsk1++];
	}
	while (wsk2 < q) {
		pom[ind++] = a[wsk2++];
	}
	FOR(i, p, q - 1) {
		a[i] = pom[i];
	}
}

int main() {
	int n = GetN();

	if (n <= GR) {
		if (MyNodeId() != 0) {
			return 0;
		}
		REP(i, n) {
			a[i] = GetElement(i);
		}
		mergeSort(0, n);
		cout << inw_cnt << endl;
		return 0;
	}
	long long poczatek = ((ll)MyNodeId() * n) / NumberOfNodes();
  	long long koniec = (((ll)MyNodeId() + 1) * n) / NumberOfNodes();
  	// cout << poczatek << ' ' << koniec << endl;
  	int nn = koniec - poczatek;
  	FOR(i, poczatek, koniec - 1) {
  		// cout << "reading: " << i << endl;
  		a[i - poczatek] = GetElement(i);
  	}
  	mergeSort(0, nn);
  	// cout << "merge sort: " << inw_cnt << endl;
  	FOR(i, koniec, n - 1) {
  		++bucketCnt[GetElement(i)];
  	}
  	// merge sort with bucket count
  	int wsk = 0;
  	ll cnt = 0;
  	REP(i, nn) {
  		while (wsk + 1 <= MAXVAL && wsk + 1 < a[i]) {
  			wsk++;
  			cnt += bucketCnt[wsk];
  		}
  		inw_cnt += cnt;
  	}
  	if (MyNodeId() > 0) {
  		// cout << "Putting to " << 0 << ' ' << inw_cnt << endl;
	  	PutLL(0, inw_cnt);
	  	Send(0);
	  	return 0;
	}
  	ll res = inw_cnt;
  	FOR(i, 1, NumberOfNodes() - 1) {
  		// cout << "gonna receive from: " << i << endl;
  		Receive(i);
  		ll chunkRes = GetLL(i);
  		res += chunkRes;
  	}
  	cout << res << endl;
}