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#include <iostream>
#include <queue>
#include <vector>
#include <fstream>
#include <cstring>
using namespace std;
const int maxn = 505;
int dp[2][maxn][maxn];
int main() {
    ios_base::sync_with_stdio(false);
    int n, k;
    cin >> n >> k;
    
    memset(dp, 0, sizeof dp);
    vector<int> v(n);
    
    for(int i = 0; i < n; i++) {
        cin >> v[i];
    }
    dp[0][0][0] = 1;
    for(int at = 0; at < n; at++) {
        int next_at = 1 - (at % 2);
        int current_at = at % 2;
        for(int sum = 0; sum <= k; sum++) {
            for(int k_sum = 0; k_sum <= sum; k_sum++) {
                dp[next_at][sum][k_sum] = dp[current_at][sum][k_sum];
                if(sum >= v[at]) {
                    dp[next_at][sum][k_sum] |= dp[current_at][sum - v[at]][k_sum];
                    if(k_sum >= v[at]) {
                        dp[next_at][sum][k_sum] |= dp[current_at][sum - v[at]][k_sum - v[at]];
                    }
                }
            }
        }
    }
    vector<int> res;
    for(int i = 0; i <= k; i++) {
        if(dp[(n % 2)][k][i]) {
            res.push_back(i);
        }
    }
    cout << (int) res.size() << endl;
    for(int i = 0; i < res.size(); i++) {
        cout << res[i] << " ";
    }
    return 0;
}