// need
#include <iostream>
#include <algorithm>
// data structure
#include <bitset>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <utility>
#include <vector>
#include <complex>
//#include <deque>
#include <valarray>
#include <unordered_map>
#include <unordered_set>
#include <array>
// etc
#include <cassert>
#include <cmath>
#include <functional>
#include <iomanip>
#include <chrono>
#include <random>
#include <numeric>

// input
#define INIT std::ios::sync_with_stdio(false);std::cin.tie(0);
#define VAR(type, ...)type __VA_ARGS__;MACRO_VAR_Scan(__VA_ARGS__);
template<typename T> void MACRO_VAR_Scan(T& t) { std::cin >> t; }
template<typename First, typename...Rest>void MACRO_VAR_Scan(First& first, Rest& ...rest) { std::cin >> first; MACRO_VAR_Scan(rest...); }
#define VEC_ROW(type, n, ...)std::vector<type> __VA_ARGS__;MACRO_VEC_ROW_Init(n, __VA_ARGS__); for(int w_=0; w_<n; ++w_){MACRO_VEC_ROW_Scan(w_, __VA_ARGS__);}
template<typename T> void MACRO_VEC_ROW_Init(int n, T& t) { t.resize(n); }
template<typename First, typename...Rest>void MACRO_VEC_ROW_Init(int n, First& first, Rest& ...rest) { first.resize(n); MACRO_VEC_ROW_Init(n, rest...); }
template<typename T> void MACRO_VEC_ROW_Scan(int p, T& t) { std::cin >> t[p]; }
template<typename First, typename...Rest>void MACRO_VEC_ROW_Scan(int p, First& first, Rest& ...rest) { std::cin >> first[p]; MACRO_VEC_ROW_Scan(p, rest...); }
#define VEC(type, c, n) std::vector<type> c(n);for(auto& i:c)std::cin>>i;
#define MAT(type, c, m, n) std::vector<std::vector<type>> c(m, std::vector<type>(n));for(auto& R:c)for(auto& w:R)std::cin>>w;
// output
#define OUT(dist) std::cout<<(dist);
#define FOUT(n, dist) std::cout<<std::fixed<<std::setprecision(n)<<(dist);
#define SOUT(n, c, dist) std::cout<<std::setw(n)<<std::setfill(c)<<(dist);
#define SP std::cout<<" ";
#define TAB std::cout<<"\t";
#define BR std::cout<<"\n";
#define SPBR(w, n) std::cout<<(w + 1 == n ? '\n' : ' ');
#define ENDL std::cout<<std::endl;
#define FLUSH std::cout<<std::flush;
#define SHOW(dist) {std::cerr << #dist << "\t:" << (dist) << "\n";}
#define SHOWVECTOR(v) {std::cerr << #v << "\t:";for(const auto& xxx : v){std::cerr << xxx << " ";}std::cerr << "\n";}
#define SHOWVECTOR2(v) {std::cerr << #v << "\t:\n";for(const auto& xxx : v){for(const auto& yyy : xxx){std::cerr << yyy << " ";}std::cerr << "\n";}}
#define SHOWQUEUE(a) {auto tmp(a);std::cerr << #a << "\t:";while(!tmp.empty()){std::cerr << tmp.front() << " ";tmp.pop();}std::cerr << "\n";}
#define SHOWSTACK(a) {auto tmp(a);std::cerr << #a << "\t:";while(!tmp.empty()){std::cerr << tmp.top() << " ";tmp.pop();}std::cerr << "\n";}
// utility
#define ALL(a) (a).begin(),(a).end()
#define FOR(w, a, n) for(int w=(a);w<(n);++w)
#define RFOR(w, a, n) for(int w=(n)-1;w>=(a);--w)
#define REP(w, n) for(int w=0;w<int(n);++w)
#define RREP(w, n) for(int w=int(n)-1;w>=0;--w)
#define IN(a, x, b) (a<=x && x<b)
template<class T> inline T CHMAX(T & a, const T b) { return a = (a < b) ? b : a; }
template<class T> inline T CHMIN(T& a, const T b) { return a = (a > b) ? b : a; }
// test
template<class T> using V = std::vector<T>;
template<class T> using VV = V<V<T>>;

template<typename S, typename T>
std::ostream& operator<<(std::ostream& os, std::pair<S, T> p) {
	os << "(" << p.first << ", " << p.second << ")"; return os;
}

#define random_shuffle "USE std::shuffle!";

// type/const
#define int ll
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using PAIR = std::pair<int, int>;
using PAIRLL = std::pair<ll, ll>;
constexpr int INFINT = (1 << 30) - 1;                    // 1.07x10^ 9
constexpr int INFINT_LIM = (1LL << 31) - 1;              // 2.15x10^ 9
constexpr ll INFLL = 1LL << 60;                          // 1.15x10^18
constexpr ll INFLL_LIM = (1LL << 62) - 1 + (1LL << 62);  // 9.22x10^18
constexpr double EPS = 1e-10;
constexpr int MOD = 1000000007;
constexpr double PI = 3.141592653589793238462643383279;
template<class T, size_t N> void FILL(T(&a)[N], const T & val) { for (auto& x : a) x = val; }
template<class ARY, size_t N, size_t M, class T> void FILL(ARY(&a)[N][M], const T & val) { for (auto& b : a) FILL(b, val); }
template<class T> void FILL(std::vector<T> & a, const T & val) { for (auto& x : a) x = val; }
template<class ARY, class T> void FILL(std::vector<std::vector<ARY>> & a, const T & val) { for (auto& b : a) FILL(b, val); }
// ------------>8------------------------------------->8------------

int dy4[] = { -1, 0, 1, 0 };
int dx4[] = { 0, 1, 0, -1 };

void calc(int k, int x, int y) {
	int sum = std::abs(x) + std::abs(y);
	if (k % 2 == 0 && sum % 2 == 1) {
		OUT(-1)BR;
		return;
	}
	int nx = 0, ny = 0;
	auto calc = [&](int tx, int ty) {
		return std::abs(nx - tx) + std::abs(ny - ty);
	};
	auto calc2 = [&](int tx, int ty, int tx2, int ty2) {
		return std::abs(tx2 - tx) + std::abs(ty2 - ty);
	};
	V<PAIR> a;
	auto push = [&](int tx, int ty) {
		a.emplace_back(tx, ty);
		nx = tx;
		ny = ty;
	};
	auto gofast = [&] {
		bool f = false;
		int sum = calc(x, y);
		if (!f) {
			int dx = x;
			int tsum = calc(dx, ny);
			if (tsum <= k) {
				int rest = k - tsum;
				if (calc2(dx, ny + rest, x, y) == sum - k) {
					push(dx, ny + rest);
					f = true;
				}
				else if (calc2(dx, ny - rest, x, y) == sum - k) {
					push(dx, ny - rest);
					f = true;
				}
			}
		}
		if (!f) {
			int dy = y;
			int tsum = calc(nx, dy);
			if (tsum <= k) {
				int rest = k - tsum;
				if (calc2(nx + rest, dy, x, y) == sum - k) {
					push(nx + rest, dy);
					f = true;
				}
				else if (calc2(nx - rest, dy, x, y) == sum - k) {
					push(nx - rest, dy);
					f = true;
				}
			}
		}
		if (!f) {
			REP(d, 4) {
				int dx = nx + dx4[d] * k;
				int dy = ny + dy4[d] * k;
				if (sum - k == calc2(dx, dy, x, y)) {
					a.emplace_back(dx, dy);
					nx = dx;
					ny = dy;
					break;
				}
			}
		}
	};
	while (nx != x || ny != y) {
		sum = calc(x, y);
		if (sum % k == 0) {
			gofast();
		}
		else if (sum > k) {
			int t = 0;
			while ((sum + 2 * t) % k != 0) ++t;
			bool f = false;
			for (int dx : {nx + t, nx - t}) for (int dy : {ny + (k - t), ny - (k - t)}) {
				if (!f && calc(dx, dy) == k && calc2(dx, dy, x, y) % k == 0 && calc2(dx, dy, x, y) < sum) {
					push(dx, dy);
					f = true;
				}
			}
			for (int dy : {ny + t, ny - t}) for (int dx : {nx + (k - t), nx - (k - t)}) {
				if (!f && calc(dx, dy) == k && calc2(dx, dy, x, y) % k == 0 && calc2(dx, dy, x, y) < sum) {
					push(dx, dy);
					f = true;
				}
			}
			for (int dx : {nx + t, nx - t}) for (int dy : {ny + (k - t), ny - (k - t)}) {
				if (!f && calc(dx, dy) == k && calc2(dx, dy, x, y) % k == 0) {
					push(dx, dy);
					f = true;
				}
			}
			for (int dy : {ny + t, ny - t}) for (int dx : {nx + (k - t), nx - (k - t)}) {
				if (!f && calc(dx, dy) == k && calc2(dx, dy, x, y) % k == 0) {
					push(dx, dy);
					f = true;
				}
			}
		}
		else {
			if (sum % 2 == 0) {
				int t = (2 * k - sum) / 2;
				bool f = false;
				for (int dx : {nx + t, nx - t}) for (int dy : {ny + (k - t), ny - (k - t)}) {
					if (!f && calc(dx, dy) == k && calc2(dx, dy, x, y) % k == 0) {
						push(dx, dy);
						f = true;
					}
				}
				for (int dy : {ny + t, ny - t}) for (int dx : {nx + (k - t), nx - (k - t)}) {
					if (!f && calc(dx, dy) == k && calc2(dx, dy, x, y) % k == 0) {
						push(dx, dy);
						f = true;
					}
				}
			}
			else {
				REP(d, 4) {
					int dx = nx + dx4[d] * k;
					int dy = ny + dy4[d] * k;
					if (calc2(dx, dy, x, y) == sum + k) {
						push(dx, dy);
						break;
					}
				}
			}
		}
	}
	{
		REP(i, a.size() - 1) {
			assert(calc2(a[i].first, a[i].second, a[i + 1].first, a[i + 1].second));
		}
	}

	OUT(a.size())BR;
	REP(i, a.size()) {
		OUT(a[i].first)SP OUT(a[i].second)BR;
	}
}

signed main() {
	INIT;

	VAR(int, k, x, y);
	calc(k, x, y);
	return 0;
}

Measured memory_bytes: 5484