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

import (
	"fmt"
	"sort"
)

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

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

		arr := make([]int, N+1)
		for i := 1; i <= N; i++ {
			fmt.Scan(&arr[i])
		}
		sort.Ints(arr)

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

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

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

using namespace std;

int main(){

	int n,m;
	while(cin>>n>>m&&!(n==0&&m==0)){
		int scores[1001];
		vector<int> comb;
		for(int i = 0; i < n; i++){
			cin>>scores[i];
		}
		scores[n]=0;
		for(int i = 0; i < n+1; i++){
			for(int j = 0; j < n+1; j++){
				int sum=scores[i]+scores[j];
				if(sum<=m)
					comb.push_back(sum);
			}
		}
		sort(comb.begin(),comb.end());
		comb.erase(unique(comb.begin(),comb.end()));

		int maxNum=0;
		for(int i = 0; i < n; i++){
			for(int j = 0; j < n; j++){
				int left = (scores[i]+scores[j]);
				if(left<=m&&comb[0]+left<=m){
					vector<int>::iterator it = lower_bound(comb.begin(),comb.end(),m-left);
					if(it==comb.end()){
						maxNum=max(maxNum,comb[comb.size()-1]+left);
					}
					else{
						if(*it==(m-left)){
							maxNum=m;
						}
						else{
							it--;
							maxNum=max(maxNum,*it+left);
						}
					}
				}
			}
		}
		cout<<maxNum<<endl;
	}

	return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
 
#define REP(i,s,n) for(int i=s;i<n;++i)
#define rep(i,n) REP(i,0,n)
#define SORT(c) sort((c).begin(),(c).end())
#define IINF INT_MAX
#define LLINF LLONG_MAX
 
typedef long long ll;
typedef pair<int, int> ii;

#define DEBUG false

int main(){

	ll n, m;
	while(cin >> n >> m){
		if(n == 0 && m == 0) break;
		vector<ll> p(n+1);
		rep(i, n) cin >> p[i];
		
		rep(i, n){
			REP(j, i, n){
				p.push_back(p[i] + p[j]);
			}
		}
		
		SORT(p);
		
		ll ans = 0;

		rep(i, p.size()){
			auto it2 = upper_bound(p.begin(), p.end(), m - p[i]);
			if(it2 == p.begin()) continue;
			it2--;
			if(p[i] > *it2) break;
			ans = max(ans, p[i] + *it2);
		}
		
		cout << ans << endl;
		
	}
	
	return 0;
}

C++: #include<iostream>
#include<string>
#include<cmath>
#include<queue>
#include<map>
#include<set>
#include<list>
#include<iomanip>
#include<vector>
#include<functional>
#include<algorithm>
#include<cstdio>
using namespace std;
typedef long long ll;
int main() {
	ll a[1000], n, m;
	while (cin >> n >> m&&n != 0 && m != 0) {
		for (int i = 0; i < n; i++) cin >> a[i];
		sort(a, a + n);
		int t = 0;
		for (t; t < n; t++) {
			if (a[t] > m) break;
		}
		t--;
		long long sum = 0;
		for (int i = t; i >= 0; i--) {
			sum = max(sum, a[i]);
			for (int j = i; j >= 0; j--) {
				if (a[i] + a[j] <= m) {
					sum = max(sum, a[i] + a[j]);
					for (int x = j; x >= 0; x--) {
						if (a[i] + a[j] + a[x] <= m) {
							sum = max(a[i] + a[j] + a[x], sum);
							for (int y = x; y >= 0; y--) {
								if (a[i] + a[j] + a[x] + a[y] <= m) {
									sum = max(a[i] + a[j] + a[x] + a[y], sum);
								}
							}
						}
					}
				}
			}
		}
	stop:;
		cout << sum << endl;
	}
}

C++: #include<cstdio>
#include<algorithm>
#include<iostream>
#include<vector>
#include<set>
#include<queue>

using namespace std;

#define rep(i,n) for(int i=0;i<int(n);i++)
#define reps(i,n) for(int i=1;i<=int(n);i++)

#define f first
#define s second

int main(){
	while(1){
		int n,m;
		cin>>n>>m;
		
		if(n==0)break;
		
		vector<int> ya;
		ya.push_back(0);
		
		rep(i,n){
			int a;
			cin>>a;
			ya.push_back(a);
		}
		
		vector<int> y2;
		rep(i,ya.size()){
			rep(j,ya.size()){
				y2.push_back(ya[i]+ya[j]);
			}
		}
		
		sort(y2.begin(),y2.end());
		
		
		int maxi=0;
		
		rep(i,y2.size()){
			vector<int>::iterator a = (lower_bound(y2.begin(),y2.end(),(m-y2[i]+1))-1);
			maxi= max(maxi,y2[i]+*a);
		}
		printf("%d\n",maxi);
	}
}

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<int> a,b,c;
		int ans =0;
		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]);
			}
		}
		rep(i,a.size())
		{
			rep(l,a.size())
			{
				int j=a[i]+a[l];
				if(j<=m&&j>ans)ans=j;
				//c.push_back(a[i]+a[l]);
			}
		}
		//sort(c.begin(),c.end());
		//cout<<*(upper_bound(c.begin(),c.end(),m)-1)<<endl;
		cout<<ans<<endl;
	}

}

C++: #include <iostream>
#include <sstream>
#include <vector>
#include <list>
#include <string>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <algorithm>
#include <numeric>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <climits>
using namespace std;

typedef int INT;
typedef vector <INT> VI;
typedef set <INT> SI;

INT P[1002];
INT Q[1002001];

INT solve( int N, INT M ) {
    INT answer = 0;
    for ( int i = 0; i < N; ++ i ) {
        int q = Q[i];
        int L = i;
        int R = N;
        INT m = M - q;
        while ( L < R ) {
            int p = ( R - L ) / 2 + L;
            INT t = q + Q[p];
            if ( t <= M ) answer = max( answer, t );
            if ( Q[p] > m ) {
                R = p - 1;
            } else {
                L = p + 1;
            }
        }
    }
    return answer;
}

int main() {
    int n, m;
    while ( cin >> n >> m ) {
        if ( n == 0 && m == 0 ) break;
        for ( int i = 0; i < n; ++ i ) {
            INT p;
            cin >> p;
            P[i] = p;
        }
        P[n] = 0;
        for ( int i = 0; i < n + 1; ++ i ) {
            for ( int j = 0; j < n + 1; ++ j ) {
                Q[i * ( n + 1 ) + j] = P[i] + P[j];
            }
        }
        int length = ( n + 1 ) * ( n + 1 );
        sort( Q, Q + length );
        cout << solve( length, m ) << endl;
    }
    return 0;
}