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#include "message.h"
#include "teatr.h"
#include "bits/stdc++.h"
using namespace std;

#define MP make_pair
#define PB push_back
#define ST first
#define ND second
#define ALL(x) (x).begin(),(x).end()
#define SZ(x) ((int)(x).size())
//#define int LLI
#define FOR(i,a,b) for(int i = (a); i <= (b); ++i)
#define REP(i,n) FOR(i,0,(int)(n)-1)
#define F1(i,n) FOR(i,1,n)

typedef long long LLI;
typedef unsigned long long LLU;
typedef long double LD;
typedef pair<int, int> pii;
typedef pair<LLI, LLI> pll;
typedef vector<int> vi;

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...);
}
#define dbg(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#define dbgV(R) {cerr << #R << "=["; for(int e : R) cerr << e << ", "; cerr << "E]\n";}
#define dbgA(R, n) {cerr << #R << "=["; for(int i = 0; i <= n; ++i) cerr << R[i] << ", "; cerr << "E]\n";}
#define boost ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)

const int MX = 1e6 + 7;
int fenwick[MX];
int cnt[MX], suf[MX];

inline void insert(int x){
	for(int i = x; i < MX; i += (i & (-i))) ++fenwick[i];
}

inline int query(int x){
	int wyn = 0;
	for(int i = x; i > 0; i -= (i & (-i))) wyn += fenwick[i];
	return wyn;
}

int32_t main(){
	const int n = GetN();
	const int ID = MyNodeId(), ile = NumberOfNodes();
	const int bs = (n + ile - 1) / ile;
	const int l = ID * bs, r = min(n - 1, (ID + 1) * bs - 1);
	
	if(l >= n) return 0;

	LLI wyn = 0;
	for(int i = r; i >= l; --i){
		int a = GetElement(i);
		wyn += query(a - 1);
		if(i > l) insert(a);
	}
	
	if(ID != 0){
        PutLL(0, wyn);
        Send(0);
    }
    else{
		int K = 0;
		REP(nr, ile){
			for(int i = K; i > 0; --i) suf[i] = suf[i + 1] + cnt[i];
			int l1 = (nr * bs), r1 = min(n - 1, (nr + 1) * bs - 1);
			if(l1 < n && l1 <= r1){ 
				FOR(i, l1, r1){
					int a = GetElement(i); 
					K = max(K, a); 
					++cnt[GetElement(i)];
					wyn += suf[a + 1];
				}
			}
			else break;
		}
		for(int i = 1; i * bs < n; ++i){
            Receive(i);
            wyn += GetLL(i);
        }
        cout << wyn;
	}
}