#include <atcoder/all>
#include <bits/stdc++.h>
#define rep(i, a, b) for (ll i = (ll)(a); i < (ll)(b); i++)
using namespace atcoder;
using namespace std;

typedef long long ll;

int n;

ll f(ll x, int i) { return (x * (1LL << i) + 1) % (1LL << n); }

void out(vector<int> a) {
    cout << a.size() << endl;
    for (auto x : a) {
        cout << x << ' ';
    }
    cout << endl;
}

int main() {
    ll x, y;
    cin >> n >> x >> y;
    vector<int> ans;
    if (x == y) {
        out(ans);
        return 0;
    }
    if (y == 0) {
        cout << -1 << endl;
        return 0;
    }
    if (y % 2) {
        cout << -1 << endl;
        return 0;
    }
    vector<int> bits;
    rep(i, 0, 61) {
        if (y & (1LL << i)) {
            bits.push_back(i);
        }
    }
    x = 1;
    ans.push_back(n);
    reverse(bits.begin(), bits.end());
    rep(i, 0, bits.size() - 1) { ans.push_back(bits[i] - bits[i + 1]); }
    out(ans);
    // rep(i, 0, ans.size()) { x = f(x, ans[i]); }
    // assert(x == y);
}