#pragma region Template
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
using vi = vector<int>;
using vll = vector<ll>;
using vvi = vector<vector<int>>;
using vvll = vector<vector<ll>>;
using vvvi = vector<vector<vector<int>>>;
using vpi = vector<pair<int,int>>;
using vpll = vector<pair<ll,ll>>;
using vs = vector<string>;
using vb = vector<bool>;
using pi = pair<int,int>;
using pll = pair<ll,ll>;
template<typename T> using spq = priority_queue<T, vector<T>, greater<T>>;
template<typename T> using gpq = priority_queue<T>;
#define fi first
#define se second
#define pb push_back
#define fore(p,a) for (auto p : a)
#define overload4(a,b,c,d,name,...) name
#define rep1(n) for (ll i = 0; i < ll(n); ++i)
#define rep2(i,n) for (ll i = 0; i < ll(n); ++i)
#define rep3(i,a,b) for (ll i = a; i < ll(b); ++i)
#define rep4(i,a,b,c) for (ll i = a; i < ll(b); i += c)
#define rep(...) overload4(__VA_ARGS__,rep4,rep3,rep2,rep1)(__VA_ARGS__)
#define rrep1(n) for (ll i = n; i--;)
#define rrep2(i,n) for (ll i = n; i--;)
#define rrep3(i,a,b) for (ll i = b; i-- > (a);)
#define rrep4(i,a,b,c) for (ll i = (a) + ((b) - (a) - 1) / (c) * (c); i >= (a); i -= c)
#define rrep(...) overload4(__VA_ARGS__,rrep4,rrep3,rrep2,rrep1)(__VA_ARGS__)
#define all(container) begin(container), end(container)
#define rall(container) rbegin(container), rend(container)
#define Vvll(name,row,column) vvll name(row, vll (column))
#define Max(...) max({__VA_ARGS__})
#define Min(...) min({__VA_ARGS__})
#define fin exit(0)
#define FASTIO ios::sync_with_stdio(false); cin.tie(nullptr)
#define FLOUT cout << setprecision(15) << fixed
#ifdef LOCAL
#define debug(x) cerr << "[DEBUG] " << __LINE__ << ": " << #x << " = " << x << endl
#else
#define debug(x)
#endif
constexpr int INF = 1001001001;
constexpr ll LINF = 1LL << 60;
const double PI = acos(-1);
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
ll fact(ll x) { return x == 0 ? 1 : x * fact(x - 1); }
ll comb(ll n, ll r) { if (r < 0 || n < r) return 0; ll ret = 1; for (ll i = 1; i <= r; i++) { ret *= n; n--; ret /= i; } return ret; }
// void prfl(double x) { printf("%.15f\n", x); }
bool ise(ll x) { return x % 2 == 0; }
bool dv(ll waru, ll warareru) { return warareru % waru == 0; }
int ci(char c) { return c - '0'; }
char ic(int i) { return '0' + i; }
int Yes(bool f=1) { cout << (f ? "Yes" : "No") << '\n'; return 0; }
int No() { Yes(0); return 0; }
template<class T> int printvec(vector<T> v) { for (int i = 0; i < (int) v.size(); i++) cout << (i ? " " : "") << v[i]; cout << '\n'; return 0; }
#pragma endregion

#include <atcoder/segtree.hpp>
signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n;
    ll s;
    cin >> n >> s;
    ll sm = 0;
    vi ans;
    for (int i = n; sm < s; i--) {
        if (sm + i <= s) sm += i, ans.push_back(i);
    }
    reverse(all(ans));
    cout << ans.size() << '\n';
    printvec(ans);
}