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#include <iostream>
#include "message.h"
#include "dzialka.h"

#define MIN_ROWS 10
#define MIN_COLS 10
#define PHASE_TRESHOLD 25000000LL

int divceil(int a, int b) {
	return (a + b - 1) / b;
}

using namespace std;
typedef pair<int, int> pii;
typedef long long ll;

int nodes;
int id;

bool rotate = false;
int width, height;
pii parts;
pii columns;
int phase_count;

int ** up;
int * zero_row;
ll counter = 0;

bool is_usable(int y, int x) {
	return rotate ? IsUsableCell(x, y) : IsUsableCell(y, x);
}

pii make_column(int index) {
	return pii(
		index * columns.second,
		min(width, (index+1) * columns.second)
	);
}

void send_last_row(pii column, int row) {
	int next_id = (id+1) % nodes;

	for (int i = column.first; i < column.second; i++) {
		PutInt(next_id, up[row][i]);
	}
	Send(next_id);
}

void get_zero(pii column) {
	int prev_id = (id + nodes - 1) % nodes;
	Receive(prev_id);
	for (int i = column.first; i < column.second; i++) {
		zero_row[i] = GetInt(prev_id);
	}
}

void fill_missing_col(pii column, int range_size) {
	for (int i = column.first; i < column.second; i++) {
		int pv = zero_row[i];
		for (int j = 0; j < range_size && up[j][i] == -1; j++) {
			up[j][i] = ++pv;
		}
	}
}

pii decide_parts() {
	int max_part_height = PHASE_TRESHOLD / width;
	if (max_part_height * nodes >= height) {
		int part_height = max(divceil(height, nodes), MIN_ROWS);
		return pii(divceil(height, part_height), part_height);
	}

	int min_part_count = divceil(height, max_part_height);
	return pii(min_part_count, divceil(height, min_part_count));
}

void prep() {
	up = new int*[parts.second];
	for (int i = 0; i < parts.second; i++) {
		up[i] = new int[width];
	}

	zero_row = new int[width]();

	int max_cols = 900 / phase_count;
	columns.second = max(MIN_COLS, divceil(width, max_cols));
	columns.first = divceil(width, columns.second);
}

void prefill(pii range, int range_size) {
	if (id > 0) {
		for (int i = 0; i < width; i++) {
			zero_row[i] = -1;
		}
	}

	for (int i = 0; i < width; i++) {
		int a = zero_row[i];
		for (int j = 0; j < range_size; j++) {
			if (is_usable(range.first + j, i)) {
				if (a != -1) a++;
			} else {
				a = 0;
			}

			up[j][i] = a;
		}
	}
}

bool is_filled(pii col_range, int last_row) {
	for (int i = col_range.first; i < col_range.second; i++) {
		if (up[last_row][i] == -1) return false;
	}

	return true;
}

void fill_missing(pii range, int range_size) {
	int col_idx = 0;
	bool send_next = range.second < height;
	while (col_idx < columns.first) {
		pii col_range = make_column(col_idx);

		bool dependency = send_next && !is_filled(col_range, range_size-1);

		if (send_next && !dependency) {
			send_last_row(col_range, range_size-1);
		}

		if (id > 0) {
			get_zero(col_range);
			fill_missing_col(col_range, range_size);

			if (dependency) {
				send_last_row(col_range, range_size-1);
			}
		}

		col_idx++;
	}
}

void count_rectangles(int range_size) {
	for (int j = 0; j < range_size; j++) {
		for (int si = 0; si < width; si++) {
			int far = height * 2;
			for (int i = si; i < width; i++) {
				far = min(far, up[j][i]);
				if (far == 0) break;
				counter += far;
			}
		}
	}
}

void do_phase(int phase) {
	int index = phase * nodes + id;
	if (index >= parts.first) return;

	pii range = pii(
		index * parts.second,
		min((index+1) * parts.second, height)
	);

	int range_size = range.second - range.first;

	prefill(range, range_size);
	fill_missing(range, range_size);
	count_rectangles(range_size);

	if (id == 0 && phase + 1 < phase_count) {
		int col_idx = 0;
		while (col_idx < columns.first) {
			get_zero(make_column(col_idx));
			col_idx++;
		}
	}
}

void sum_up() {
	if (id == 0) {
		ll total_counter = counter;
		for (int i = 1; i < min(nodes, parts.first); i++) {
			Receive(i);
			total_counter += GetLL(i);
		}

		cout << total_counter << endl;
	} else {
		PutLL(0, counter);
		Send(0);
	}
}

int main() {
	ios_base::sync_with_stdio(0);

	id = MyNodeId();
	nodes = NumberOfNodes();

	height = GetFieldHeight();
	width = GetFieldWidth();

	if (width > height) {
		rotate = true;
		swap(width, height);
	}

	parts = decide_parts();
	phase_count = divceil(parts.first, nodes);
	if (id >= parts.first) return 0;

	prep();

	for (int i = 0; i < phase_count; i++) {
		do_phase(i);
	}

	sum_up();

	return 0;
}