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#include <iostream>
#include <cstdio>
#include <string>
#include <sstream> 
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <cmath>
#include <algorithm>
#include <cstring>
#include <ctime>
#include <cassert>

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

using namespace std;
using ll = long long;

const ll INF = 1e9+10;
const int MASTER = 0;
const int MAX_VAL = 1e6+10;

// Test Tomasz Nowak
/*
int GetN() { return int(1e8); }
int GetElement(int i) { return (i * 1ll * i) % int(1e6) + 1; }
*/

// Test Mateusz Lewko 1
/*
int GetN() { return 100 * 1000 * 1000; }
int GetElement(int i) {
return 1 + (((ll)i * 27) + i & (i %113) + ((i % 37) ^ (i % 20)) * 3571) % 1000000;
}
*/

// Test Mateusz Lewko 2
/*
int GetN() { return 100 * 1000 * 1000; }
int GetElement(int i) { 
if (i < 100 * 1000 * 1000 - 3) return 1 + i / 100;
else return 100 * 1000 * 1000 - i;
}
*/

int bt[MAX_VAL+10];

int bt_query(int x) {
    int res = 0;
    ++x;
    while (x > 0) {
        res += bt[x];
        x -= (x & (-x));
    }
    return res;
}
void bt_increment(int x) {
    ++x;
    while (x <= MAX_VAL+1) {
        ++bt[x];
        x += (x & (-x));
    }
}

int cnt[MAX_VAL+10];
int larger[MAX_VAL+10];

int main()
{
    const int id = MyNodeId();
    const int n = GetN();
    const int k = min(n, NumberOfNodes());

    //don't need such instances
    if (id >= k) return 0;

    const int block_len = ceil(n / (double)k);
    const int range_begin = id*block_len;
    const int range_end = min(n-1, (id+1)*block_len-1);
    const int range_len = range_end-range_begin+1;

    // computing local result
    ll inv_count = 0;

    // bit tree variant from the end, so with one query instead of two
    for (int i = range_end; i >= range_begin; --i) {
        int x = GetElement(i);
        inv_count += bt_query(x-1);
        bt_increment(x);
    }

    PutLL(MASTER, inv_count);
    Send(MASTER);

    if (id == MASTER) {
        // joining results
        ll res = 0;
        for (int sender_id = 0; sender_id < k; ++sender_id) {
            Receive(sender_id);
            ll sender_result = GetLL(sender_id);
            res += sender_result;
        }

        for (int block_start = 0; block_start < n; block_start += range_len) {
            for (int i = block_start; i < min(n, block_start+range_len); ++i) {
                int x = GetElement(i);
                res += larger[x];
                ++cnt[x];
            }
            for (int x = MAX_VAL; x >= 0; --x) {
                larger[x] = larger[x+1] + cnt[x+1];
            }
        }
        printf("%lld\n", res);
    }
    return 0;
}