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// Jedna instancja wypisuje maksymalny wzrost.

#include "message.h"
#include "teatr.h"
#include <algorithm>
#include "bits/stdc++.h"

#define FOR(i, n) for(int i = 0, __n = n; i < __n; i++)
using namespace std;
const int MINE = 1;
const int MAXE = 1000021;

int NodeNo;
int NodeCount;
int A, B;
int n;


int* val;

long long counter[MAXE];
long long larger[MAXE];
long long smaller[MAXE];

long long merger(int* to, int* t1, int m1, int* t2, int m2) {
  long long tot = 0;
  int a1 = 0;
  int a2 = 0;
  while (a1 + a2 < m1 + m2) {
    bool first;
    if (a1 == m1) {
      first = false;
    } else if(a2 == m2) {
      first = true;
    } else if(t1[a1] > t2[a2]) {
      first = false;
    } else {
      first = true;
    }

    if (first) {
      to[a1 + a2] = t1[a1];
      a1++;
      tot += a2;
    } else {
      to[a1 + a2] = t2[a2];
      a2++;
    }
  }
  // cerr << "MERGING:" << endl;
  // for (int i = 0; i<m1; i++) {
  //   cerr << t1[i] << " ";
  // }
  // cerr << " with ";
  // for (int i = 0; i<m2; i++) {
  //   cerr << t2[i] << " ";
  // }
  // cerr << " = " << tot << endl;
  return tot;
}

long long inversions(int* arr, int m) {
  long long tot = 0;
  int* T1 = new int[m];
  int* T2 = new int[m];
  FOR(i, m) T1[i] = arr[i];

  int len = 1;

  while (len < m) {
    for (int a = 0; a < m; a += 2 * len) {
      int alen = min(a + len, m) - a;
      int b = min(a + len, m);
      int blen = min(b + len, m) - b;
      tot += merger(T2 + a, T1 + a, alen, T1 + b, blen);
    }
    // cerr << "TOT" << tot << endl;
    swap(T1, T2);
    len *= 2;
  }

  delete [] T1;
  delete [] T2;
  return tot;
}


int main() {
  NodeNo = MyNodeId();
  NodeCount = NumberOfNodes();
  n = GetN();
  int space = (n + NodeCount - 1) / NodeCount;
  A = min(space * NodeNo, n);
  B = min(space * (NodeNo + 1), n);
  val = new int[B-A];

  long long total = 0;

  for (int i = A; i < B; i++) {
    int el = GetElement(i);
    val[i - A] = el;
    counter[el]++;
  }
  
  for (int i = 1; i < MAXE; i++) {
    smaller[i] = smaller[i-1] + counter[i-1];
  }
  for (int i = MAXE-2; i >= 0; i--) {
    larger[i] = larger[i+1] + counter[i+1];
  }
  
  for (int i = 0; i < A; i++) {
    int el = GetElement(i);
    total += smaller[el];
  }
  // for (int i = B; i < n; i++) {
  //   int el = GetElement(i);
  //   total += larger[el];
  // }

  // cerr << NodeNo << ") " << A << "-" << B << " ext:" << total << endl;
  total += inversions(val, B - A);
  // cerr << "INT " << total << endl;

  // cerr << NodeNo << ") " << A << "-" << B << " " << total << endl;

  if (NodeNo == 0) {
    for (int i = 1; i < NodeCount; i++) {
      Receive(i);
      total += GetLL(i);
    }
    cout << total << endl;
  } else {
    PutLL(0, total);
    Send(0);
  }
  delete [] val;
}