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#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;

#define FOR(i,a,n) for (auto i ## __ = (n), i = (a); i <= i ## __; ++i)
#define FORD(i,a,n) for (auto i ## __ = (n), i = (a); i >= i ## __; --i)
#define REP(i,n) FOR(i,0, n - 1)
#define ALL(h) begin(h), end(h)
#define EB emplace_back
#define X first
#define Y second
#define V vector
#define tpv typedef V<

typedef long long LL;
typedef pair<int, int> PII;
tpv int> VI;
tpv VI> VVI;
tpv PII> VPII;
tpv LL> VLL;

constexpr char nl = '\n';
#define endl nl
#define ris return *this
#define tem template<class t

tem, class u> inline void mini(t& a, u&& b) { if (b < a) a = b; }
tem, class u> inline void maxi(t& a, u&& b) { if (b > a) a = b; }
int ceil2(int h) { return h < 2 ? 1 : 1 << (sizeof(h) * 8 - __builtin_clz(h - 1)); }

tem> struct Dump { t a, b; };
tem> auto dump(t&& h) -> Dump<decltype(begin(h))> { return {ALL(h)}; }
tem> auto stub(t* h) -> decltype(cerr << *h, 0);
tem> char stub(...);
#define enif(o) tem> typename enable_if<sizeof stub<t>(0) o 1, debug&>::type operator<<(t h)
#define dor > debug& operator<<
struct debug {
#ifdef DEBUG
#define deb debug()
	~debug() { cerr << nl; }
	enif(!=) { cerr << boolalpha << h; ris; }
	enif(==) {
		*this << '{';
		for (auto a = begin(h), b = end(h); a != b;)
			*this << *a++ << &" "[a == b];
		ris << '}';
	}
	tem, class u dor(pair<t, u> p) { ris << '(' << p.X << ", " << p.Y << ')'; }
	tem dor(Dump<t> d) {
		*this << "{\n";
		for (t a = d.a, c = a; a != d.b; ++a)
			*this << "  " << distance(c, a) << ": " << *a << nl;
		ris << '}';
	}
#else
	operator int() { return 0; }
#define deb 0 and debug()
	tem dor(t&&) { ris; }
#endif
};

#define imie(h...) #h ": " << (h) << " "
#define LOG(h...) deb << imie(h)
#define DOG(h...) deb << #h ": " << dump(h) << " "
// End of templates

void bucket_sort(VI& v) {
	VI cnt(1e6 + 1);
	for (int x : v)
		++cnt[x];
	FOR (i, 1, (int)cnt.size() - 1)
		cnt[i] += cnt[i - 1];

	VI res(v.size());
	for (int x : v)
		res[cnt[x - 1]++] = x;
	v = res;
}

LL count_inv(VI const& a, VI const& b) {
	LL res = 0;
	int i = 0, j = 0;
	while (i < (int)a.size() and j < (int)b.size()) {
		if (a[i] <= b[j])
			++i;
		else {
			++j;
			res += (int)a.size() - i;
		}
	}

	return res;
}

LL merge_sort(VI& v, int beg, int end) {
	if (beg + 1 >= end)
		return 0;

	LL res = 0;
	int mid = (beg + end) >> 1;
	res += merge_sort(v, beg, mid);
	res += merge_sort(v, mid, end);

	// LL prediction = res + count_inv({v.begin() + beg, v.begin() + mid}, {v.begin() + mid, v.begin() + end});

	VI tmp(v.begin() + beg, v.begin() + mid);
	int i = 0, j = mid, k = beg;
	for (;;) {
		if (i == (int)tmp.size())
			break; // all is in its place
		if (j == end) {
			copy(tmp.begin() + i, tmp.end(), v.begin() + k);
			break;
		}

		if (tmp[i] <= v[j])
			v[k++] = tmp[i++];
		else {
			v[k++] = v[j++];
			res += (int)tmp.size() - i;
		}
	}

	// assert(prediction == res);
	return res;
}

LL count_inv(VI& v) { return merge_sort(v, 0, v.size()); }

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

// // int GetN() { return 1000; }
// int GetN() { return 100*1000*1000; }
// int GetElement(int i) { return 1 + (GetN() - i) % 1000000; }

PII segment_interval(int segment_id, int segments_no, int n) {
	int beg = LL(segment_id) * n / segments_no;
	int end = LL(segment_id + 1) * n / segments_no;
	return {beg, end};
}

VI read_segment(int segment_id, int segments_no, int n) {
	int beg, end;
	tie(beg, end) = segment_interval(segment_id, segments_no, n);
	LOG(MyNodeId()) imie(beg) imie(end);

	VI v(end - beg);
	FOR (i, beg, end - 1)
		v[i - beg] = GetElement(i);
	return v;
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	int N = GetN();
	int non = NumberOfNodes();
	int pid = MyNodeId();

	// TODO: below segment choosing does not work
	int k = sqrt(non);
	int seg_a = (pid / k) % k;
	int seg_b = pid % k;

	LOG(pid) imie(seg_a) imie(seg_b) imie(k);

	if (seg_a > seg_b)
		swap(seg_a, seg_b);

	LL res = 0;
	if (seg_a == seg_b) {
		auto v = read_segment(seg_a, k, N);
		// LOG(pid) imie(v);
		res += count_inv(v);
		LOG(pid) imie(res);
	} else {
		auto a = read_segment(seg_a, k, N);
		auto b = read_segment(seg_b, k, N);
		bucket_sort(a);
		bucket_sort(b);
		// LOG(pid) imie(a) imie(b);
		res += count_inv(a, b);
		LOG(pid) imie(res);
	}

	if (pid > 0) {
		PutInt(0, seg_a);
		PutInt(0, seg_b);
		PutLL(0, res);
		Send(0);
		return 0;
	}

	// pid == 0
	V<VLL> results(k, VLL(k));
	results[seg_a][seg_b] = res;
	REP (i, non - 1) {
		int sender = Receive(-1);
		int a = GetInt(sender);
		int b = GetInt(sender);
		res = GetLL(sender);
		results[a][b] = res;
	}

	res = 0;
	REP (i, k)
		FOR (j, i, k - 1)
			res += results[i][j];

	cout << res << nl;

	return 0;
}