#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define F first
#define S second
#define pii pair<int, int>
#define eb emplace_back
#define all(v) v.begin(), v.end()
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep3(i, l, n) for (int i = l; i < (n); ++i)
#define sz(v) (int)v.size()
#define endl '\n'
const int inf = 1e9 + 7;
const ll INF = 1e18;
int mod = 998244353;
// int mod = 1000000007;
#define abs(x) (x >= 0 ? x : -(x))
#define lb(v, x) (int)(lower_bound(all(v), x) - v.begin())
#define ub(v, x) (int)(upper_bound(all(v), x) - v.begin())
template<typename T1, typename T2> inline bool chmin(T1 &a, T2 b) { if (a > b) { a = b; return 1; } return 0; }
template<typename T1, typename T2> inline bool chmax(T1 &a, T2 b) { if (a < b) { a = b; return 1; } return 0; }
ll gcd(ll a, ll b) { if (b == 0) return a; return gcd(b, a % b); }
ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }
ll pow(ll a, int b) { return b ? pow(a * a, b / 2) * (b % 2 ? a : 1) : 1; }
ll modpow(ll a, ll b, ll _mod) { return b ? modpow(a * a % _mod, b / 2, _mod) * (b % 2 ? a : 1) % _mod : 1; }
template<class T, class U> ostream& operator << (ostream& os, const pair<T, U>& p) { os << p.F << " " << p.S; return os; }
template<class T> ostream& operator << (ostream& os, const vector<T>& vec) { rep(i, sz(vec)) { if (i) os << " "; os << vec[i]; } return os; }
template<typename T> inline istream& operator >> (istream& is, vector<T>& v) { rep(j, sz(v)) is >> v[j]; return is; }
template<class T, class T2> inline void add(T &a, T2 b) { a += b; if (a >= mod) a -= mod; }


void solve();

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cout << fixed << setprecision(10);
    
    int T;
    // cin >> T;
    T = 1;
    
    while (T--) {
        solve();
    }
}

// pdf editorial
void solve() {
    int k;
    cin >> k;
    int x, y;
    cin >> x >> y;
    if (k % 2 == 0 && (x + y) % 2) {
        cout << -1 << endl;
        return;
    }
    int xflg = 0, yflg = 0, swapflg = 0;
    if (x < 0) { xflg = 1; x = -x; }
    if (y < 0) { yflg = 1; y = -y; }
    if (x < y) { swapflg = 1; swap(x, y); }
    vector<pii> ans;
    int nx = 0, ny = 0;
    if ((x + y) % k == 0) {
        while (1) {
            int tmp = min(k, x - nx);
            nx += tmp;
            ny += k - tmp;
            if (nx == x && ny == y) break;
            ans.eb(nx, ny);
        }
    } else if (x + y < k && (x + y) % 2) {
        ny -= k - x;
        nx = x;
        ans.eb(nx, ny);
        int tmp = (k + x - y) / 2;
        nx += tmp;
        ny += k - tmp;
        ans.eb(nx, ny);
    } else {
        int c = k - ((x + y) % k);
        int n;
        if (x + y < k && (x + y) % 2 == 0) n = 2;
        else {
            n = (x + y + (k - 1)) / k;
            if (c % 2) n++;
        }
        int sum = 0;
        int g = (k * n - x - y) / 2;
        while (sum + k < g) {
            ny -= k;
            ans.eb(nx, ny);
            // cout << "n0 " << nx << " " << ny << endl;
            sum += k;
        }
        int rest = g - sum;
        ny -= rest;
        nx += k - rest;
        ans.eb(nx, ny);
        // cout << "n1 " << nx << " " << ny << endl;
        rest = x - (k - rest);
        while (rest >= k) {
            nx += k;
            rest -= k;
            ans.eb(nx, ny);
            // cout << "n2 " << nx << " " << ny << endl;
        }
        nx += rest;
        ny += k - rest;
        if (ny == y) {
            
        } else {
            ans.eb(nx, ny);
            // cout << "n3 " << nx << " " << ny << endl;
            while (1) {
                ny += k;
                if (ny == y) break;
                ans.eb(nx, ny);
            }
        }
    }
    
    ans.eb(x, y);
    rep(i, sz(ans)) {
        if (swapflg) swap(ans[i].F, ans[i].S);
        if (xflg) ans[i].F *= -1;
        if (yflg) ans[i].S *= -1;
    }
    cout << sz(ans) << endl;
    rep(i, sz(ans)) cout << ans[i] << endl;
}



Measured memory_bytes: 3952