/*{{{*/
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<string>
#include<iostream>
#include<sstream>
#include<set>
#include<map>
#include<queue>
#include<bitset>
#include<vector>
#include<limits.h>
#include<assert.h>
#define SZ(X) ((int)(X).size())
#define ALL(X) (X).begin(), (X).end()
#define REP(I, N) for (int I = 0; I < (N); ++I)
#define REPP(I, A, B) for (int I = (A); I < (B); ++I)
#define FOR(I, A, B) for (int I = (A); I <= (B); ++I)
#define FORS(I, S) for (int I = 0; S[I]; ++I)
#define RS(X) scanf("%s", (X))
#define SORT_UNIQUE(c) (sort(c.begin(),c.end()), c.resize(distance(c.begin(),unique(c.begin(),c.end()))))
#define GET_POS(c,x) (lower_bound(c.begin(),c.end(),x)-c.begin())
#define CASET int ___T; scanf("%d", &___T); for(int cs=1;cs<=___T;cs++)
#define MP make_pair
#define PB push_back
#define MS0(X) memset((X), 0, sizeof((X)))
#define MS1(X) memset((X), -1, sizeof((X)))
#define LEN(X) strlen(X)
#define F first
#define S second
using namespace std;
typedef long long LL;
typedef unsigned long long ULL;
typedef long double LD;
typedef pair<int,int> PII;
typedef vector<int> VI;
typedef vector<LL> VL;
typedef vector<PII> VPII;
typedef pair<LL,LL> PLL;
typedef vector<PLL> VPLL;
template<class T> void _R(T &x) { cin >> x; }
void _R(int &x) { scanf("%d", &x); }
void _R(LL &x) { scanf("%lld", &x); }
void _R(double &x) { scanf("%lf", &x); }
void _R(char &x) { scanf(" %c", &x); }
void _R(char *x) { scanf("%s", x); }
void R() {}
template<class T, class... U> void R(T &head, U &... tail) { _R(head); R(tail...); }
template<class T> void _W(const T &x) { cout << x; }
void _W(const int &x) { printf("%d", x); }
void _W(const LL &x) { printf("%lld", x); }
void _W(const double &x) { printf("%.16f", x); }
void _W(const char &x) { putchar(x); }
void _W(const char *x) { printf("%s", x); }
template<class T,class U> void _W(const pair<T,U> &x) {_W(x.F); putchar(' '); _W(x.S);}
template<class T> void _W(const vector<T> &x) { for (auto i = x.begin(); i != x.end(); _W(*i++)) if (i != x.cbegin()) putchar(' '); }
void W() {}
template<class T, class... U> void W(const T &head, const U &... tail) { _W(head); putchar(sizeof...(tail) ? ' ' : '\n'); W(tail...); }
#ifdef HOME
 #define DEBUG(...) {printf("# ");printf(__VA_ARGS__);puts("");}
#else
 #define DEBUG(...)
#endif
int MOD = 1e9+7;
void ADD(LL& x,LL v){x=(x+v)%MOD;if(x<0)x+=MOD;}
/*}}}*/
const int SIZE = 1e6+10;
LL f(int X,int Y,int K){
    int s=abs(X)+abs(Y);
    if(s==K)return 1;
    int need=max(2,(s+K-1)/K);
    while(need*K<s||(need*K-s)%2)need++;
    return need;
}
int dx[4]={1,0,-1,0};
int dy[4]={0,1,0,-1};
int main(){
    int K,X,Y;
    R(K,X,Y);
    if(K%2==0&&(X+Y)%2)W(-1);
    else{
        PII now={0,0};
        int need=f(X,Y,K);
        W(need);
        REPP(i,1,need){
            bool suc=0;
            REP(j,4){
                if(f(X-(now.F+dx[j]*K),Y-(now.S+dy[j]*K),K)==need-i){
                    now=MP(now.F+dx[j]*K,now.S+dy[j]*K);
                    suc=1;
                    break;
                }
            }
            if(!suc&&abs(X-now.F)<K){
                int r=K-(X-now.F);
                PII nxt=MP(X,now.S+r);
                if(f(X-nxt.F,Y-nxt.S,K)==need-i){
                    now=nxt;
                    suc=1;
                }
                else{
                    nxt=MP(X,now.S-r);
                    if(f(X-nxt.F,Y-nxt.S,K)==need-i){
                        now=nxt;
                        suc=1;
                    }
                }
            }
            if(!suc&&abs(Y-now.S)<K){
                int r=K-(Y-now.S);
                PII nxt=MP(now.F+r,Y);
                if(f(X-nxt.F,Y-nxt.S,K)==need-i){
                    now=nxt;
                    suc=1;
                }
                else{
                    nxt=MP(now.F-r,Y);
                    if(f(X-nxt.F,Y-nxt.S,K)==need-i){
                        now=nxt;
                        suc=1;
                    }
                }
            }
            if(!suc){
                if(need==i+1){
                    // 2K-abs(now.S-Y)=2x-now.F-X
                    if(now.S!=Y){
                        int x=(2*K-abs(now.S-Y)+now.F+X)/2;
                        if(x-min(now.F,X)<=K){
                            if(now.S<Y)now=MP(x,now.S+(K-(x-now.F)));
                            else now=MP(x,now.S-(K-(x-now.F)));
                            suc=1;
                        }
                    }
                    if(!suc){
                        int y=(2*K-abs(now.F-X)+now.S+Y)/2;
                        if(y-min(now.S,Y)<=K){
                            if(now.F<X)now=MP(now.F+(K-(y-now.S)),y);
                            else now=MP(now.F-(K-(y-now.S)),y);
                            suc=1;
                        }
                    }
                }
            }
            /*
            if(!suc){
                REP(j,4){
                    FOR(k,1,K-1){
                        int nx=now.F+dx[j]*k+dx[(j+1)&3]*(K-k);
                        int ny=now.S+dy[j]*k+dy[(j+1)&3]*(K-k);
                        if(f(X-nx,Y-ny,K)==need-i){
                            now=MP(nx,ny);
                            suc=1;
                            break;
                        }
                    }
                    if(suc)break;
                }
            }
            */
            W(now);

        }
        W(X,Y);

    }
    return 0;
}



Measured memory_bytes: 2304