Go: ///
// File:  0529.go
// Author: ymiyamoto
//
// Created on Wed Feb 28 20:39:28 2018
//
package main

import (
	"fmt"
	"sort"
)

func max(n, m int64) int64 {
	if n < m {
		return m
	} else {
		return n
	}
}

func main() {
	for {
		var N int
		var M int64
		fmt.Scan(&N, &M)
		if N == 0 && M == 0 {
			break
		}

		arr := make([]int64, N+1)
		for i := 1; i <= N; i++ {
			fmt.Scan(&arr[i])
		}
		sort.Slice(arr, func(i, j int) bool { return arr[i] < arr[j] })

		sums := make([]int64, len(arr)*len(arr))
		for i := 0; i < len(arr); i++ {
			for j := 0; j < len(arr); j++ {
				sums[i*len(arr)+j] = arr[i] + arr[j]
			}
		}

		sort.Slice(sums, func(i, j int) bool { return sums[i] < sums[j] })
		var m int64 = 0
		for _, val := range sums {
			rem := M - val
			if rem >= 0 {
				index := sort.Search(len(sums), func(i int) bool { return sums[i] > rem }) - 1
				if index >= 0 {
					m = max(m, val+sums[index])
				}
			}
		}
		fmt.Println(m)
	}
}

C++: #include<algorithm>
#include<vector>

#define MAX_N 1001

using namespace std;

class CNum{
public:
	vector<int> v;
};

bool Find(vector<int> &v, int search){
	for(unsigned int i = 0; i < v.size(); i++){
		if( v[i] == search ){
			return true;
		}
	}
	return false;
}

int main(void){
	while( 1 ){
		int n, m;
		int V[MAX_N] = {0,};
		CNum D[4];
		int Max = 0;

		cin >> n >> m;

		if( n == 0 && m == 0 ){
			break;
		}

		for(int i = 0; i < n; i++){
			cin >> V[i];
		}

		sort(V, V + n);
		reverse(V, V + n);

		for(int i = 0; i < n; i++){
			for(int j = 0; j < 4; j++){
				if( j == 0 ){
					D[j].v.push_back( V[i] );
				}else if( j > 0 ){
					D[j].v.clear();
					for(unsigned int l = 0; l < D[j - 1].v.size(); l++ ){
						int tmp = V[i] + D[j - 1].v[l];
						if( tmp <= m ){
							int index = -1;
							
							for(int k = 0; k < n; k++){
								if( tmp + V[k] <= m ){
									index = k;
									break;
								}
							}
							if( index >= 0 && tmp + V[index] >= Max && !Find(D[j].v, tmp) ){
								if( Max < tmp ){
									Max = tmp;
								}
								D[j].v.push_back( tmp );
							}
						}
					}
				}
			}
		}

		for(int i = 0; i < 4; i++){
			//cout << " " << j << ":" << '\n';
			for(unsigned int j = 0; j < D[i].v.size(); j++ ){
				//cout << D[j].v[k] << ' ';
				int tmp = D[i].v[j];
				if( tmp <= m && Max < tmp){
					Max = tmp;
				}
			}
			//cout << '\n';
		}
		cout << Max << '\n';
	}
	return 0;
}

C++: #include<iostream>
#include<vector>
#include<map>
#include<utility>
#include<algorithm>
#include<queue>
#include<stack>
#include<string>
#include<stdlib.h>
#include<stdio.h>
#include<cmath>
#include<cstdlib>
#include<typeinfo>
#include<sstream>
#include<list>
#include<set>
#define rep(i,n) for(int i=0;i<(int)n;i++)
#define fori(i,k,n) for(int i=k;i<(int)n;i++)
using namespace std;
int in()
{
	int x;cin>>x;
	return x;
}
int stringInt(string a)
{
	return atoi(a.c_str());
}
string intString(int a)
{
	stringstream ss;
	ss<<a;
	return ss.str();
}
vector<int> SieveOfEratosthenes(int x)
{
	vector<int> a;
	vector<int> b(x+1,0);
	for(int i=2;i<=x;i++)
	{
		if(b[i]==0)
		{
			a.push_back(i);
			for(int l=i;l<=x;l+=i)
			{
				b[l]=1;
			}
		}
	}
	return a;
}

int main ()
{
	int n,m;
	while(cin>>n>>m&&n&&m)
	{
		vector<long long > a,b;
		b.push_back(0);
		rep(i,n)
		{
			b.push_back(in());
		}
		rep(i,n+1)
		{
			rep(l,n+1)
			{
				a.push_back(b[i]+b[l]);
			}
		}
		long long ans = 0;
		sort(a.begin(),a.end());
		rep(i,a.size())
		{
			vector<long long>::iterator t=upper_bound(a.begin(),a.end(),m-a[i]);
			if(t==a.begin())continue;
			t--;
			ans=max(ans,*t+a[i]);
		}
		cout<<ans<<endl;


	}

}

C++: #include<stdio.h>
#include<stdio.h>
#include<bits/stdc++.h>
#include<vector>
#define int long long int
#define rep(a,b,c) for(int a=b;a<c;a++)
using namespace std;
void a1(){
    int i, len = 3;
    char str[] = "abc";
    for(i=0;i<len;i++){
        printf("%c\n",str[2-i]);
    }
    return;
}

int length(char str[5]){
    int cut=0;
    while(*(str+cut)!='\0'){
        cut++;
    }
    return cut;
}

void a2(){
    char a[4][5]={"ab","cdef","g","hij"};
    int i;
    for(i=0; i<4; i++){
        printf("%d\n",length(a[i]));
    }
    return;
}

void a3(){
    char str[4];
    strcpy(str,"abc");
    printf("%s\n",str);
    return;
}

void a4(){
    char a[7]="saitou",b[7] = "suzuki";
    int i;

    for(i=0;i<7;i++){
        int k = a[i]-b[i];
        if(k > 0){
            printf("%c",a[i]);
        }else if(k < 0){
            printf("%c",b[i]);
        }else{
            printf("0");
        }
    }
    printf("\n");
    return;
}

void a5(){
    char *a[3];
    int n,i,j,cut = 0;
    for(i=0;i<3;i++){
        scanf("%d",&n);
        a[i]=(char *)malloc((n+1)*sizeof(char));
        scanf("%s",a[i]);
    }
    for(i=0;i<3;i++){
        for(j=0;j<strlen(a[i]);j++){
            if(a[i][j]=='P'||a[i][j]=='p'){
                cut++;
            }
        }
    }
    printf(">> %d\n",cut);
    for(i=0;i<3;i++){
        free(a[i]);
    }
}

void y(){
    int n,m;
    vector<int> v,v2;
    while(1){
    cin >> n >> m;
    v.clear();v2.clear();
    if(n==0&&m==0)break;
    v.push_back(0);
    rep(i,0,n){
        int x;cin >> x;
        v.push_back(x);
    }
    rep(i,0,v.size()){
        rep(j,0,v.size()){
            v2.push_back(v[i]+v[j]);
        }
    }
    v2.erase(unique(v2.begin(),v2.end()),v2.end());
    sort(v2.begin(),v2.end());
    int ans=0,k=0;
    //cout << v2.size() << " a " <<  endl;
    bool a=false;
    for(int j=v2.size()-1;j>=0;j--){
        rep(i,k,v2.size()){
            k=i;
            if(v2[i]+v2[j]>m){
                //if(i==(j-1))a=true;
                break;
            }
        ans=max(ans,v2[i]+v2[j]);
        //    cout << an << " a " << endl;
        }
        if(k>j)break;
    }
    cout << ans << endl;
    }
    return;
}

signed main(){
    y();
    return 0;
}

C++: #include <bits/stdc++.h>
#define rep(i,l,n) for(int i=l;i<n;i++)
#define rer(i,l,n) for(int i=l;i<=n;i++)
#define all(a) a.begin(),a.end()
#define o(a) cout<<a<<endl
#define pb(a) push_back(a)
#define mk(a,b) make_pair(a,b)
#define fi first
#define se second
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> pii;

int n,m,ans,MAX;
vi d(1010);

void solve(int sc,int k){
	if(sc>m) return;
	MAX=max(MAX,sc);
	if(k==n) return;
	rep(i,0,n+1){
		solve(sc+d[i],k+1);
	}
}

int main(){
	while(1){
		ans=0,MAX=0;
		cin>>n>>m;
		if(n==0 && m==0) break;
		d[0]=0;
		rep(i,1,n+1) cin>>d[i];
		sort(all(d));
		reverse(all(d));
		solve(0,0);
		o(MAX);
	}
}