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#include "dzialka.h"
#include "message.h"

#include <iostream>
#include <stack>
#include <utility>

int width;
int height;
int my_min_y;
int my_max_y;
int my_height;
int ** t;
bool * fully_computed;
int * incoming;
std::stack<std::pair<int, int> > S;
int number_of_nodes;

void init() {
  t = new int*[width];
  fully_computed = new bool[width];
  incoming = new int[width];
  for (int i = 0; i < width; i++) {
    t[i] = new int[my_height];
    fully_computed[i] = false;
    incoming[i] = 0;
  }
  for (int i = 0; i < width; i++) {
    t[i][0] = 0;
  }
  for (int i = 0; i < my_height; i++) {
    t[0][i] = 0;
  }
}

void compute_t() {
  for (int i = 0; i < width; i++) {
    for (int j = 0; j < my_height; j++) {
      if (IsUsableCell(i,j + my_min_y)) {
        if (j == 0) {
          t[i][j] = 1;
        } else {
          t[i][j] = t[i][j-1] + 1;
        }
      } else {
        t[i][j] = 0;
        fully_computed[i] = true;
      }
    }
  }
}

void compute_t_again() {
  if (MyNodeId() == 0) {
    return;
  }
  int end = my_height - 1;
  if (MyNodeId() == number_of_nodes - 1) {
    end = my_height;
  }
  for (int i = 0; i < width; i++) {
    for (int j = 0; j < end; j++) {
      if (t[i][j] == 0) {
        break;
      }
      t[i][j] += incoming[i];
    }
  }
}

int min(int a, int b) {
  return a < b ? a : b;
}

long long compute() {
  long long result = 0;
  long long part = 0;
  for (int j = 0; j < my_height; j++) {
    S = std::stack<std::pair<int, int> >();
    part = 0;
    for (int i = 0; i < width; i++) {
      if (t[i][j] == 0) {
        S = std::stack<std::pair<int, int> >();
        part = 0;
      } else if (S.empty()) {
        S.push(std::make_pair(t[i][j], 1));
        part = t[i][j];
        result += part;
      } else {
        int count = 1;
        int h = t[i][j];
        while (!S.empty() && S.top().first >= h) {
          count += S.top().second;
          part -= ((long long)S.top().first) * S.top().second;
          S.pop();
        }
        S.push(std::make_pair(h, count));
        part += ((long long)h) * count;
        result += part;
      }
    }
    //printf("ID=%d row=%d result=%lld\n", MyNodeId(), j + my_min_y, result);
  }
  return result;
}

void compute_node_stats() {
  int h = height / number_of_nodes;
  if (height % number_of_nodes != 0) {
    h++;
  }
  my_min_y = h * MyNodeId();
  my_max_y = min(height, h * (MyNodeId() + 1));
  my_height = my_max_y - my_min_y;
}

int message_size = 1000;

void send_to(int target) {
  for (int j = 0; j < width; j+= message_size) {
    for (int i = j; i < j + message_size && i < width; i++) {
      PutInt(target, t[i][my_height-1]);
    }
    Send(target);
  }
}

void receive(int from) {
  for (int j = 0; j < width; j += message_size) {
    Receive(from);
    for (int i = j; i < j + message_size && i < width; i++) {
      incoming[i] = GetInt(from);
    }
  }
}

void compute_last_row() {
  for (int i = 0; i < width; i++) {
    if (!fully_computed[i]) {
      t[i][my_height-1] += incoming[i];
    }
  }
}
/*
void print_my_array() {
  printf("I'm %d\n", MyNodeId());
  for (int i = 0; i < my_height; i++) {
    for (int j = 0; j < width; j++) {
      printf("%d ", t[j][i]);
    }
    printf("\n");
  }
}*/

void send_heights() {
  if (MyNodeId() == 0) {
    send_to(1);
  } else {
    for (int i = 1; i < number_of_nodes; i++) {
      if (MyNodeId() == i) {
        receive(i - 1);
        if (MyNodeId() < number_of_nodes - 1) {
          compute_last_row();
          send_to(i + 1);
        }
      }
    }
  }
}

void gather_results(long long my_result) {
  //printf("I'm %d and my result is %lld\n", MyNodeId(), my_result);
  if (MyNodeId() == 0) {
    unsigned long long res = my_result;
    for (int i = 1; i < number_of_nodes; i++) {
      Receive(i);
      res += GetLL(i);
    }
    std::cout << res << "\n";
  } else {
    PutLL(0, my_result);
    Send(0);
  }
}

int main() {
  width = GetFieldHeight();
  height = GetFieldWidth();
  number_of_nodes = min(50, NumberOfNodes());
  if (MyNodeId() >= number_of_nodes) {
    return 0;
  }
  if (height < 200 || number_of_nodes == 1) {
    if (MyNodeId() != 0) {
      return 0;
    }
    my_min_y = 0;
    my_max_y = height;
    my_height = height;
    init();
    compute_t();
    long long result = compute();
    std::cout << result << "\n";
    //print_my_array();
  } else {
    compute_node_stats();
    init();
    compute_t();
    send_heights();
    compute_t_again();
    long long result = compute();
    gather_results(result);
    return 0;
  }
}