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#include "bits/stdc++.h"
#include "message.h"
#include "teatr.h"

using namespace std;
#define PB push_back
#define LL long long
#define int LL
#define FOR(i,a,b) for (int i = (a); i <= (b); i++)
#define FORD(i,a,b) for (int i = (a); i >= (b); i--)
#define REP(i,n) FOR(i,0,(int)(n)-1)
#define st first
#define nd second
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())
#define VI vector<int>
#define PII pair<int,int>
#define LD long double

template<class C> void mini(C& a4, C b4) { a4 = min(a4, b4); }
template<class C> void maxi(C& a4, C b4) { a4 = max(a4, b4); }

template<class TH> void _dbg(const char *sdbg, TH h){cerr<<sdbg<<"="<<h<<"\n";}
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
  while(*sdbg!=',')cerr<<*sdbg++;cerr<<"="<<h<<","; _dbg(sdbg+1, a...);
}

template<class T> ostream &operator<<(ostream &os, vector<T> V){
  os<<"[";for(auto vv:V)os<<vv<<",";return os<<"]";
} 

template<class L, class R> ostream &operator<<(ostream &os, pair<L,R> P) {
  return os << "(" << P.st << "," << P.nd << ")";
}


#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif

struct CTree{
  VI t;
  CTree(){
    t.resize(1 << 20);
  }
  void inc(int x){
    while(x < SZ(t)){
      t[x]++;
      x += x & -x;
    }
  }
  int get(int x){
    int res = 0;
    while(x){
      res += t[x];
      x ^= x & -x;
    }
    return res;
  }
};

int top_div(int n, int k){
  return (n + k - 1) / k;
}

void load_block(int n, int BLOCK_SIZE, int idx, VI & acc){
  int block_begin = BLOCK_SIZE * idx;
  int block_end = BLOCK_SIZE * (idx + 1);
  mini(block_end, n);
  FOR(i, block_begin, block_end - 1){
    acc[GetElement(i)]++;
  }
}

int32_t main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int n = GetN();
  int node_id = MyNodeId();
  int BLOCK_SIZE = top_div(n, 10);
  int block_begin = BLOCK_SIZE * node_id;
  int block_end = BLOCK_SIZE * (node_id + 1);
  mini(block_end, n);
  CTree tree;
  int res = 0;
  FORD(i, block_end - 1, block_begin){
    int el = GetElement(i);
    res += tree.get(el - 1);
    tree.inc(el);
  }
  int left = node_id / 10;
  int right = node_id % 10;
  if(left < right){
    VI acc(1 << 20);
    VI acc2(1 << 20);
    load_block(n, BLOCK_SIZE, left, acc);
    load_block(n, BLOCK_SIZE, right, acc2);
    partial_sum(ALL(acc2), acc2.begin());
    FOR(i, 1, 1000000){
      res += acc2[i - 1] * acc[i];
    }
  }
  PutLL(0, res);
  Send(0);
  if(node_id == 0){
    res = 0;
    int nodes = NumberOfNodes();
    REP(i, nodes){
      Receive(i);
      res += GetLL(i);
    }
    cout<<res<<"\n";
  }
}