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#include <algorithm>
#include <vector>
#include <queue>
#include <cstdio>
#include <cstring>

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

#define ll long long
#define PII pair<int,int>
#define VP vector< PII >

const int IS = sizeof(int);
const int TH = 5000000;
const int MIL = 1234567;

using namespace std;

ll merge(int* a, int from, int mid, int to, int* b) {
  ll res = 0;
  int i = from;
  int j = mid;
  for(int k=from;k<to;k++) {
    if(i < mid && (j >= to || a[i] <= a[j])) {
      b[k] = a[i];
      i++;
    } else {
      res += mid-i;
      b[k] = a[j];
      j++;
    }
  }
  return res;
}

ll solve(int* b, int from, int to, int* a) {
  if(to - from < 2) {
    return 0;
  }
  int mid = (from + to) / 2;
  ll res = 0;
  res += solve(a, from, mid, b);
  res += solve(a, mid, to, b);
  res += merge(b, from, mid, to, a);
  return res;
}

ll solve(int* a, int n) {
  int* b = new int[n];
  memcpy(b,a,n*IS);
  return solve(a,0,n,b);
}

ll solveSmall(int from, int to) {
  int s = to - from;
  int* a = new int[s];
  for(int i=0;i<s;i++) {
    a[i] = GetElement(from + i);
  }
  return solve(a, s);
}

ll solveBig(int from, int to) {
  int mid = (from + to) / 2;
  int* lo = new int[MIL];
  int* hi = new int[MIL];
  ll* slo = new ll[MIL];
  memset(lo,0,MIL*IS);
  memset(hi,0,MIL*IS);
  memset(slo,0,MIL*sizeof(ll));
  for(int i=from;i<mid;i++) {
    lo[GetElement(i)]++;
  }
  for(int i=MIL-2;i>=0;i--) {
    slo[i] = slo[i+1] + lo[i];
  }
  for(int i=mid;i<to;i++) {
    hi[GetElement(i)]++;
  }
  int i = 1;
  int j = 1;
  ll res = 0;
  while(i < MIL && j < MIL) {
    while(i < MIL && lo[i] == 0) {
      i++;
    }
    while(j < MIL && hi[j] == 0) {
      j++;
    }
    if(i < MIL && j < MIL) {
      if(i <= j) {
        i++;
      } else {
        res += hi[j]*slo[i];
        j++;
      }
    }
  }
  return res;
}

int isBig(PII& p) {
  return p.second - p.first > TH;
}

VP splitIntoNodes(int n) {
  VP res;
  queue<PII> q;
  q.push(make_pair(0,n));
  while(!q.empty()) {
    PII p = q.front();
    q.pop();
    res.push_back(p);
    if(isBig(p)) {
      int mid = (p.first + p.second) / 2;
      q.push(make_pair(p.first,mid));
      q.push(make_pair(mid,p.second));
    }
  }
  reverse(res.begin(), res.end());
  return res;
}

int main(int argc, char** argv) {
  int me = MyNodeId();
  int nodes = NumberOfNodes();
  int n = GetN();

  vector< PII > ps = splitIntoNodes(n);
  ll res = 0;
  if(me < ps.size()) {
    PII myWork = ps[me];
    if(isBig(myWork)) {
      res = solveBig(myWork.first, myWork.second);
    } else {
      res = solveSmall(myWork.first, myWork.second); 
    }
    if(me > 0) {
      PutLL(0, res);
      Send(0);
    }
  }

  if(me == 0) {
    for(int i=1;i<ps.size();i++) {
      Receive(i);
      res += GetLL(i);
    }
    printf("%lld\n", res);
  }
  return 0;
}