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#include "message.h"
#include "teatr.h"
#include <iostream>
#include <vector>
#include <algorithm>

constexpr int INSTANCES_NUMBER = 100;
constexpr int MAX_HEIGHT = 1000000;

long long Merge(int l, int p, std::vector<int>& arr, std::vector<int>& aux){
   int s = (l + p) / 2;
   int i = l, u = l - 1, j = s + 1, it = 0;
   long long res = 0;

   while(i <= s && j <= p) {
      if(arr[i] > arr[j]) {
         while(arr[u + 1] < arr[j] && u < i) ++u;
         res += (u - l + 1);
         aux[it++] = arr[j++];
      }
      else {
        aux[it++] = arr[i++];
      }
   }
   while(i <= s) {
     aux[it++] = arr[i++];
   }
   while(j <= p) {
      while(arr[u + 1] < arr[j] && u < s) ++u;
      res += (u - l + 1);
      aux[it++] = arr[j++];
   }
   
   for (int i = 0; i < it; i++) {
      arr[l + i] = aux[i];
   }

   return res;
   }

long long Mergesort(int l, int p, std::vector<int>& arr, std::vector<int>& aux){
   int s = (l + p) / 2;
   long long result = 0;
   if(l < p){
      result += Mergesort(l, s, arr, aux);
      result += Mergesort(s+1, p, arr, aux);
      result += Merge(l, p, arr, aux);
   }
   return result;
}

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

  int block_size = (n + INSTANCES_NUMBER - 1) / INSTANCES_NUMBER;
  int start = std::min(block_size * node_id, n);
  int end = std::min(start + block_size, n);

  std::vector<int> heights(n);
  std::vector<int> counter(MAX_HEIGHT + 1, 0);
  for (int i = 0; i < start; i++) {
    heights[i] = GetElement(n - i - 1);
    counter[heights[i]]++;
  }
  for (int i = start; i < end; i++) {
    heights[i] = GetElement(n - i - 1);
  }

  for (int i = 1; i <= MAX_HEIGHT; i++) {
    counter[i] += counter[i - 1];
  }

  std::vector<int> aux(n);
  long long result = (start < end ? Mergesort(start, end - 1, heights, aux) : 0);
  for (int i = start; i < end; i++) {
	  result += counter[heights[i] - 1];
  }

  if (node_id != 0) {
    PutLL(0, result);
    Send(0);
  } else {
    for (int i = 1; i < INSTANCES_NUMBER; i++) {
	    result += GetLL(Receive(-1));
    }
    std::cout << result << '\n';
  }

  return 0;
}