#include<bits/stdc++.h>
using namespace std;
#define rep(i,N) for(i=0;i<N;i++)
#define ll long long

int main(void){
    ll N,X,Y;
    ll x[64]={0},y[64]={0};

    ll i,j,k;

    cin>>N>>X>>Y;
    rep(i,N){
        if((X&(1LL<<i))!=0)x[i]=1;
        if((Y&(1LL<<i))!=0)y[i]=1;
    }
    reverse(x,x+N);
    reverse(y,y+N);

    rep(i,N)clog<<x[i];
    clog<<endl;
    rep(i,N)clog<<y[i];
    clog<<endl;

    ll shift=0;
    bool can=0;
    for(i=0;i<N;i++){
        bool same=1;
        for(j=0;i+j<N;j++){
            if(x[i+j]!=y[j])same=0;
        }
        if(same){
            shift=i;
            can=1;
            break;
        }
    }

    if(Y%2==0)can=0;

    ll A=1;
    vector<ll>ans;
    for(i=N-shift;i<N;i++){
        while(y[i]!=1&&A<N){A++;i++;}
        if(y[i]!=1)can=0;
        ans.push_back(A);
        A=1;
    }

    if(can){
        cout<<ans.size()<<endl;
        rep(i,ans.size())cout<<ans[i]<<' ';
        cout<<endl;
    }else cout<<-1<<endl;

    return 0;
}