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// Jedna instancja wypisuje maksymalny wzrost.

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

using namespace std;


long long* count(int begin, int end) {
  int n, j;
  long long counts[] = {0, 0, 0, 0, 0, 0};
  for(int i = begin; i < end; i++) {
    n = GetElement(i) - 1; //normalize 1-N to 0-(N-1)
    ++counts[n];
    for(j=n+1; j<5; j++) {
      counts[5] += counts[j];
    }
  }
  return counts;
}


int main() {
  int NodeId = MyNodeId();
  int NodesCount = NumberOfNodes();
  int N = GetN();
  


  if (N <= 1000000) {
    if (NodeId != 0) return 0; // exit another instances
    // n is small, compute on one instance
    long long *counts = count(0, N);
    cout << counts[5] << endl;
    return 0;
  }
  // n is big:
  int begin = (int)((long long)N * (long long)NodeId / NodesCount);
  int end = (int)((long long)N * (long long)(NodeId+1) / NodesCount);

  long long *counts = count(begin, end);

  long long prev[] = {0, 0, 0, 0, 0, 0};
  // wait for previous
  if(NodeId > 0) {
    Receive(NodeId-1);
    for(int i = 0; i < 6; i++) {
       prev[i] = GetLL(NodeId-1);
       if (i < 5) {
        for(int j = 0; j < i; j++) {
            counts[5] += (prev[i]) * (counts[j]);
        }
       }
    }
  }
  for (int i = 0; i < 6; i++) {
    counts[i] += prev[i];
  }

  // send to next nodes
  if (NodeId < (NodesCount-1)) {
    for(int i = 0; i < 6; i++) {
      PutLL(NodeId+1, counts[i]);
    }
    Send(NodeId+1);
  } else {
    // last instance, print result
    cout << counts[5] << endl;
  }
  return 0;
}