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#include "dzialka.h"
#include "message.h"
#include <bits/stdc++.h>
using namespace std;

template <typename T> ostream& operator<<(ostream& out, const vector<T>& xs) {
	out << '[';
	for (auto&& x : xs)
		out << ' ' << x;
	return out << " ]";
}

enum class DivlineDir {
	Horizontal, Vertical
};
ostream& operator<<(ostream& out, DivlineDir divdir) {
	return out << (divdir == DivlineDir::Horizontal ? "Horizontal" : "Vertical");
}

struct FieldSlice {

	int x1, y1, x2, y2;

	long long area() const {
		return static_cast<long long>(x2 - x1) * (y2 - y1);
	}
	bool canBeDivided() const {
		return area() > 1;
	}
	DivlineDir divlineDirection() const {
		return y2 - y1 >= x2 - x1 ? DivlineDir::Horizontal : DivlineDir::Vertical;
	}
	bool at(int x, int y) const {
		auto result = IsUsableCell(y1+y, x1+x);
		return result;
	}

	template <DivlineDir divdir> int divlineLength() const {
		return divdir == DivlineDir::Horizontal ? x2 - x1 : y2 - y1;
	}
	template <DivlineDir divdir> int constLineCoordinate() const {
		return divdir == DivlineDir::Horizontal ? (y1+y2)/2-y1 : (x1+x2)/2-x1;
	}
	template <DivlineDir divdir> bool atFromDivline(int index, int dist) const {
		return divdir == DivlineDir::Horizontal ? at(index, dist) : at(dist, index);
	}
	template <DivlineDir divdir> int maxDistForward() const {
		return divdir == DivlineDir::Horizontal ? y2 - y1 : x2 - x1;
	}

	template <DivlineDir divdir> FieldSlice nextLeft() const {
		return divdir == DivlineDir::Horizontal ? FieldSlice{
			.x1 = x1,
			.y1 = y1,
			.x2 = x2,
			.y2 = (y1 + y2) / 2
		} : FieldSlice {
			.x1 = x1,
			.y1 = y1,
			.x2 = (x1 + x2) / 2,
			.y2 = y2,
		};
	}
	template <DivlineDir divdir> FieldSlice nextRight() const {
		return divdir == DivlineDir::Horizontal ? FieldSlice {
			.x1 = x1,
			.y1 = (y1 + y2) / 2,
			.x2 = x2,
			.y2 = y2
		} : FieldSlice {
			.x1 = (x1 + x2) / 2,
			.y1 = y1,
			.x2 = x2,
			.y2 = y2
		};
	}

	static FieldSlice getWhole() {
		auto fs = FieldSlice{
			.x1 = 0,
			.y1 = 0,
			.x2 = ::GetFieldWidth(),
			.y2 = ::GetFieldHeight(),
		};
		return fs;
	}

};

template <typename T> struct ZRange {
	T from, to;
	ZRange(T from, T to):from(from),to(to){}
	struct Iterator {
		T index;
		Iterator& operator++() {
			++index;
			return *this;
		}
		const T& operator*() {
			return index;
		}
		bool operator!=(Iterator other) const {
			return index != other.index;
		}
	};
	Iterator begin() {
		return Iterator{from};
	}
	Iterator end() {
		return Iterator{to};
	}
	friend ostream& operator<<(ostream& out, ZRange zr) {
		return out << '[' << zr.from << ", " << zr.to << ')';
	}
};

struct MetaThreadGroup {

	int i1, i2;

	int myRelativeId() const {
		return MyNodeId() - i1;
	}
	int relativeNodeCount() const {
		return i2 - i1;
	}
	bool amAlone() const {
		return relativeNodeCount() == 1;
	}
	bool shouldGoLeftNext() const {
		return myRelativeId() < relativeNodeCount() / 2;
	}

	MetaThreadGroup nextLeft() const {
		return MetaThreadGroup { .i1 = i1, .i2 = (i1 + i2) / 2 };
	}
	MetaThreadGroup nextRight() const {
		return MetaThreadGroup { .i1 = (i1 + i2) / 2, .i2 = i2 };
	}

	ZRange<int> myRange(long long elementsCount) const {
		return ZRange<int>(
			static_cast<int>(elementsCount * (myRelativeId())) / relativeNodeCount(),
			static_cast<int>(elementsCount * (myRelativeId() + 1)) / relativeNodeCount()
		);
	}
	template <typename F> void forOthers(F f) {
		auto ithis = MyNodeId();
		for (int i=i1; i<ithis; ++i) f(i);
		for (int i=ithis+1; i<i2; ++i) f(i);
	}

	static MetaThreadGroup startingPoint() {
		return MetaThreadGroup {
			.i1 = 0,
			.i2 = NumberOfNodes(),
		};
	}

};

/*

	(0,0) (1,0) ...
	(0,1) (1,1) ...
	...   ...   ...

	..... => forward  - down  (.y += 1)
	.....    backward - up    (.y -= 1)
	-----
	.....
	.....

	..|.. => forward  - right (.x += 1)
	..|..    backward - left  (.x -= 1)
	..|..
	..|..
	..|..

*/

inline int forward(int coord) {
	return coord + 1;
}
inline int backward(int coord) {
	return coord - 1;
}

struct IndexDist {
	int forw, back;
	friend ostream& operator<<(ostream& out, IndexDist ind) {
		return out << "IndexDist(" << (ind.forw != -1 ? to_string(ind.forw) : "…") << ", " << (ind.back != -1 ? to_string(ind.back) : "…") << ")";
	}
};
template <DivlineDir divdir> vector<IndexDist> phase1(FieldSlice field, MetaThreadGroup thrgroup) {
	// compute my share
	auto linelen = field.divlineLength<divdir>();
	auto myShare = thrgroup.myRange(linelen);
	auto linepos = field.constLineCoordinate<divdir>();
	auto indexdists = vector<IndexDist>(linelen, IndexDist{-1,-1});
	for (auto lineIndex : myShare) {
		auto distForw = 0;
		auto distBack = 0;
		while (linepos+distForw < field.maxDistForward<divdir>() and field.atFromDivline<divdir>(lineIndex, linepos+distForw))
			++distForw;
		while (linepos-distBack-1 >= 0 and field.atFromDivline<divdir>(lineIndex, linepos-distBack-1))
			++distBack;
		indexdists[lineIndex] = IndexDist{ distForw, distBack };
	}
	//clog << "[" << MyNodeId() << "] " << indexdists << endl;
	// send it to other threads
	thrgroup.forOthers([&](int otherThread){
		PutInt(otherThread, myShare.from);
		PutInt(otherThread, myShare.to);
		for (auto lineIndex : myShare) {
			PutInt(otherThread, indexdists[lineIndex].forw);
			PutInt(otherThread, indexdists[lineIndex].back);
		}
		Send(otherThread);
	});
	// receive them
	thrgroup.forOthers([&](int otherThread){
		Receive(otherThread);
		auto indexFrom = GetInt(otherThread);
		auto indexTo = GetInt(otherThread);
		auto otherShare = ZRange<int>(indexFrom, indexTo);
		for (auto lineIndex : otherShare) {
			auto forw = GetInt(otherThread);
			auto back = GetInt(otherThread);
			assert(indexdists[lineIndex].forw == -1);
			assert(indexdists[lineIndex].back == -1);
			indexdists[lineIndex].forw = forw;
			indexdists[lineIndex].back = back;
		}
	});
	//clog << "[" << MyNodeId() << "] " << indexdists << endl;
	assert(none_of(indexdists.begin(), indexdists.end(), [&](IndexDist ind){ return ind.forw == -1 or ind.back == -1; }));
	return indexdists;
}

using Result = long long;
/*
   ##### ##### ###\  #####
     |   |   | |   | |   |
	 |   |   | |   | |   |
	 |   ##### ###/  #####

   LONG LONG WILL NOT HOLD
   (75000)^4 ~=~ 10^20

*/

Result phase2(const vector<IndexDist>& maxdists, MetaThreadGroup thrgroup) {
	// TODO: this spreads work unevenly, but is way simpler
	auto myShare = thrgroup.myRange(maxdists.size());
	Result subr = 0;
	for (auto i1 : myShare) {
		auto forwSoFar = maxdists[i1].forw;
		auto backSoFar = maxdists[i1].back;
		for (int i2=i1+1; i2<=static_cast<int>(maxdists.size()); ++i2) {
			forwSoFar = min(forwSoFar, maxdists[i2-1].forw);
			backSoFar = min(backSoFar, maxdists[i2-1].back);
			subr += static_cast<long long>(forwSoFar) * backSoFar;
		}
	}
	return subr;
}

template <DivlineDir divdir> Result phase3(FieldSlice field, MetaThreadGroup thrgroup) {
	if (thrgroup.amAlone()) {
		auto subr2a = solve(field.nextLeft<divdir>(), thrgroup);
		auto subr2b = solve(field.nextRight<divdir>(), thrgroup);
		return subr2a + subr2b;
	} else if (thrgroup.shouldGoLeftNext()) {
		return solve(field.nextLeft<divdir>(), thrgroup.nextLeft());
	} else {
		return solve(field.nextRight<divdir>(), thrgroup.nextRight());
	}
}

Result solve(FieldSlice field, MetaThreadGroup thrgroup) {
	if (not field.canBeDivided()) return static_cast<long long>(field.at(0, 0) and thrgroup.myRelativeId() == 0); // TODO
	auto divdir = field.divlineDirection();
	//clog << "[" << MyNodeId() << "] " << divdir << endl;
	auto maxDistances = divdir == DivlineDir::Horizontal ? phase1<DivlineDir::Horizontal>(field, thrgroup) : phase1<DivlineDir::Vertical>(field, thrgroup);
	auto subresult1 = phase2(maxDistances, thrgroup);
	auto subresult2 = divdir == DivlineDir::Horizontal ? phase3<DivlineDir::Horizontal>(field, thrgroup) : phase3<DivlineDir::Vertical>(field, thrgroup);
	return subresult1 + subresult2;
}

void processMyResult(Result result) {
	if (MyNodeId() != 0) {
		PutLL(0, result);
		Send(0);
	} else {
		for (int other=1; other<NumberOfNodes(); ++other) {
			Receive(other);
			auto otherResult = GetLL(other);
			result += otherResult;
		}
		cout << result << '\n';
	}
}

int main() {
	auto field = FieldSlice::getWhole();
	auto thrgroup = MetaThreadGroup::startingPoint();
	auto result = solve(field, thrgroup);
	processMyResult(result);
}