#include <bits/stdc++.h>

using namespace std;


#define sz(x) ((int)x.size())
#define rep(i, a, b) for (int i = (a); i < (b); i++)
#define all(x) begin(x), end(x)

typedef vector<int> vi;

typedef vector<bitset<405>> vb;
struct Maxclique {
	//double limit = 0.025, pk = 0;
	double limit = 0.0025, pk = 0;
	struct Vertex { int i, d = 0; };
	typedef vector<Vertex> vv;
	vb e;
	vv V;
	vector<vi> C;
	vi qmax, q, S, old;
	void init(vv& r) {
		for (auto& v : r) v.d = 0;
		for (auto& v : r) for (auto j : r) v.d += e[v.i][j.i];
		sort(all(r), [](auto a, auto b) { return a.d > b.d; } );
		int mxD = r[0].d;
		rep(i, 0, sz(r)) r[i].d = min(i, mxD) + 1;
	}
	void expand(vv& R, int lev = 1) {
		S[lev] += S[lev - 1] - old[lev];
		old[lev] = S[lev - 1];
		while (sz(R)) {
			if (sz(q) + R.back().d <= sz(qmax)) return;
			q.push_back(R.back().i);
			vv T;
			for (auto v : R) if (e[R.back().i][v.i]) T.push_back({v.i});
			if (sz(T)) {
				if (S[lev]++ / ++pk < limit) init(T);
				int j = 0, mxk = 1, mnk = max(sz(qmax) - sz(q) + 1, 1);
				C[1].clear(), C[2].clear();
				for (auto v : T) {
					int k = 1;
					auto f = [&](int i) { return e[v.i][i]; };
					while (any_of(all(C[k]), f)) k++;
					if (k > mxk) mxk = k, C[mxk + 1].clear();
					if (k < mnk) T[j++].i = v.i;
					C[k].push_back(v.i);
				}
				if (j > 0) T[j - 1].d = 0;
				rep(k, mnk, mxk + 1) for (int i : C[k])
					T[j].i = i, T[j++].d = k;
				expand(T, lev + 1);
			} else if (sz(q) > sz(qmax)) qmax = q;
			q.pop_back(), R.pop_back();
		}
	}
	vi maxClique() { init(V), expand(V); return qmax; }
	Maxclique(vb conn) : e(conn), C(sz(e) + 1), S(sz(C)), old(S) {
		rep(i, 0, sz(e)) V.push_back({i});
	}
};


const double EPS = 1e-6;
int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	int n;
	double r;
	cin >> n >> r;

	vector<pair<int, int>> nodes;
	for (int i = 1; i < n; i++)
		for (int j = 1; j < n; j++)
			if (min({i, j, n - i, n - j}) >= r - EPS)
				nodes.push_back({i, j});

	int N = nodes.size();
	vb conn(N);
	for (int i = 0; i < N; i++)
		for (int j = 0; j < N; j++) {
			int dx = abs(nodes[i].first - nodes[j].first);
			int dy = abs(nodes[i].second - nodes[j].second);
			if (dx * dx + dy * dy >= r * r * 4 - EPS)
				conn[i][j] = true;
		}

	vi sol;
	if (r > 1.5 + EPS) {
		sol = Maxclique(conn).maxClique();
	} else {
		for (int i = 0; i < N; i++) {
			bool ok = true;
			for (int j : sol) ok &= conn[i][j];
			if (ok) sol.push_back(i);
		}
	}
	cout << sol.size() << '\n';
	for (int i : sol) cout << nodes[i].first << ' ' << nodes[i].second << '\n';


}