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

#include <iostream>
#include <vector>
#include <cassert>
#include <cstdlib>
#include <algorithm>
#include <climits>
#include <cstdint>

using namespace std;

const int kNodes = NumberOfNodes();
const int kId = MyNodeId();

bool transposed = false;
int rows = GetFieldHeight();
int cols = GetFieldWidth();
int my_row_start;
int my_row_end;
int my_col_start;
int my_col_end;

int IsUsable(int row, int col) {
  if (!transposed) {
    return IsUsableCell(row, col);
  } else {
    return IsUsableCell(col, row);
  }
}

void SendRow(int target, int* const row) {
  for (int i = 0; i < cols; ++i) {
    PutInt(target, row[i]);
  }
  Send(target);
}

void SendOne(int target, uint64_t value) {
  PutLL(target, value);
  Send(target);
}

void ReceiveRow(int* const row) {
  const int source = Receive(-1);
  for (int i = 0; i < cols; ++i) {
    row[i] = GetInt(source);
  }
}

uint64_t ReceiveOne() {
  const int source = Receive(-1);
  return GetLL(source);
}

int T[2][75001];
int Lower[75001];
int NbLower[75001];
int Sorted[75001];

uint64_t FastSums(int start, int end, int* const row) {
  if (end <= start) {
    return 0;
  }
  if (end - start == 1) {
    return row[start];
  }
  if (end - start == 2) {
    return row[start] + row[end - 1] + min(row[start], row[end - 1]);
  }

  const int middle = (start + end) / 2;

  int s_val = INT_MAX;
  int s_idx = -1;
  for (int i = start; i < end; ++i) {
    const bool equal_better = (
        row[i] == s_val && abs(middle - i) < abs(middle - s_idx));
    if (row[i] < s_val || equal_better) {
      s_val = row[i];
      s_idx = i;
    }
  }

  if (s_idx == start || s_idx == end - 1) {
    for (int i = start; i < end; ++i) {
     Sorted[i] = row[i];
    }
    sort(Sorted + start, Sorted + end);
    
    uint64_t result = 0;
    int min_idx = start;
    while (true) {
      if (start == end) {
        return result;
      } else if (row[start] == Sorted[min_idx]) {
        result += row[start] * (end - start);
        ++start;
        ++min_idx;
      } else if (row[end - 1] == Sorted[min_idx]) {
        result += row[end - 1] * (end - start);
        --end;
        ++min_idx;
      } else {
        break;
      }
    }

    return result + FastSums(start, end, row);
  }
  
  return FastSums(start, s_idx, row) +
         FastSums(s_idx + 1, end, row) +
         (uint64_t) s_val * (s_idx - start + 1) * (end - s_idx);
}

uint64_t Solve(int r_start, int r_end, int c_start, int c_end) {
  uint64_t result = 0;
  for (int r = r_start; r < r_end; ++r) {
    for (int c = c_start; c < c_end; ++c) {
      const int usable = IsUsable(r, c);
      if (r == r_start) {
        T[r % 2][c] = usable == 0 ? 0 : NbLower[c] + usable;
      } else {
        T[r % 2][c] = usable == 0 ? 0 : T[(r + 1) % 2][c] + usable;
      }
    }
    result += FastSums(c_start, c_end, T[r % 2]);
  }
  return result;
}

void Depths(int r_start, int r_end, int c_start, int c_end) {
  for (int r = r_start; r < r_end; ++r) {
    for (int c = c_start; c < c_end; ++c) {
      const int usable = IsUsable(r, c);
      if (r == 0) {
        T[r % 2][c] = usable;
      } else {
        T[r % 2][c] = usable == 0 ? 0 : T[(r + 1) % 2][c] + usable;
      }
    }
  }
  for (int c = c_start; c < c_end; ++c) {
    Lower[c] = T[(r_end - 1) % 2][c];
  }
}

void Transpose() {
  transposed = !transposed;
  swap(rows, cols);
  swap(my_row_start, my_col_start);
  swap(my_row_end, my_col_end);
}

int main() {
  ios::sync_with_stdio(false);

  if (rows < cols) {
    Transpose();
  }

  my_row_start = kId * rows / kNodes;
  my_row_end = (kId + 1) * rows / kNodes;
  my_col_start = 0;
  my_col_end = cols;

  if ((uint64_t) cols * cols < 100000LL || kNodes == 1) {
    if (kId == 0) {
      cout << Solve(0, rows, 0, cols) << endl;
    }
  } else {
    uint64_t result = 0;

    Depths(my_row_start, my_row_end, my_col_start, my_col_end);
    
    if (kId != 0) {
      ReceiveRow(NbLower);
    }
    if (kId != kNodes - 1) {
      const int my_rows = my_row_end - my_row_start;
      for (int c = my_col_start; c < my_col_end; ++c) {
        if (Lower[c] == my_rows) {
          Lower[c] += NbLower[c];
        }
      }
      SendRow(kId + 1, Lower);
    }

    result = Solve(my_row_start, my_row_end, my_col_start, my_col_end);

    if (kId != 0) {
      SendOne(0, result);
    } else {
      for (int i = 1; i < kNodes; ++i) {
        result += ReceiveOne();
      }
      cout << result << endl;
    }
  }

  return 0;
}