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<bits/stdc++.h>
using namespace std;
vector<long int> po;
vector <pair <int ,long int> > sss;
long int n,a,low,m,lastans,memo[1005];
void solve(int dp,long int sum);

int main(){
    while(1){
        lastans=0;
        po.clear();
        //for(int i=0;i<1005;i++)memo[i]=0;

        cin >> n >> m;
        if(n==0&&m==0)break;
        for(int i=0;i<n;i++){
            cin >> a;
            po.push_back(a);
           // low=min(low,a);
        }
        sort(po.begin(),po.end());
        //cout << po[0] << endl;
        //solve(0,0);
        //lastans=po[n-1];

        for(int i=4;i>0;i--){
            for(int j=n-1;j>=0;j--){
                if(m>=i*po[j]){
                    lastans=max(i*po[j],lastans);

                    for(int k=4-i;i>0;i--){
                        for(int s=0;s<n;s++){
                            if(m>=i*po[j]+po[s]){
                                lastans=max(i*po[j]+po[s],lastans);

                                for(int t=4-k;t>0;t--){
                                    for(int u=0;u<n;u++){
                                        if(m>=i*po[j]+po[s]+po[u]){
                                         lastans=max(i*po[j]+po[s]+po[u],lastans);

                                         for(int v=4-t;v>0;v--){
                                            for(int w=u-1;w>=0;w--){
                                                if(m>=i*po[j]+po[s]+po[u]+po[w]){
                                                    lastans=max(lastans,i*po[j]+po[s]+po[u]+po[w]);
                                                    //break;
                                                }else break;
                                            }
                                         }
                                            //break;
                                        }else break;
                                    }
                                }
                                //break;
                            }else break;

                        }
                    }

                    //lastans=max(lastans,po[j]*i);
                    //break;
                }else break;
            }
        }



        cout << lastans << endl;
        //cout <<"ss=" << ss << endl;
    }

    return 0;
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main(void) {

    unsigned int N, M;
    while (cin >> N >> M, N || M) {
        vector<unsigned int> P(N+1);
        P[0] = 0;
        for (int i = 1; i <= N; i++) cin >> P[i];

        vector<unsigned int> P2;
        for (int i = 0; i <= N; i++) {
            for (int j = i; j <= N; j++) {
                P2.push_back(P[i]+P[j]);
            }
        }
        sort(P2.begin(), P2.end());

        unsigned int ans = 0;
        for (int i = 0; i < P2.size(); i++) {
            if (P2[i] > M) continue;
            unsigned int left = 0, right = P2.size()-1;
            unsigned int mid;
            for (int j = 0; j < 100; j++) {
                mid = (left+right)/2;
                if (P2[i]+P2[mid] > M) {
                    right = mid;
                } else {
                    left = mid;
                }
            }
            ans = max(ans, P2[i]+P2[mid]);
        }
        cout << ans << endl;
    }

    return 0;
}

C++: #include <iostream>
#include <string.h>
#include <algorithm>
#include <set>
#include <cstdio>
using namespace std;

int main() {
	int N, M;
	while(cin >> N >> M && (N || M)){
		int  P[1001] = {0}, ans = 0;
		for(int i = 0; i < N; ++i){
			scanf("%d", &P[i]);
		}
		set<int> darts;
		for(int i = 0; i <= N; ++i){
			for(int j = 0; j <= N; ++j){
				if(P[i] + P[j] > M)
					continue;
				darts.insert(darts.end(), P[i] + P[j]);
			}
		}
		for(int i = 0; i < N; ++i){
			for(int j = 0; j < N; ++j){
				if(P[i] + P[j] > M)
					continue;
				set<int>::iterator it = darts.lower_bound(M - (P[i] + P[j]));
				if(it == darts.end())
					--it;
				if(*it > M - (P[i] + P[j]))
					--it;
					
				ans = max(ans, P[i] + P[j] + *it);
			}
		}
		cout << ans << endl;
	}
	return 0;
}

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

using namespace std;

#define MAX(a,b) ((a)>(b)?(a):(b))

int main()
{
    int N;
    long long M;

    cin >> N >> M;

    while(N!=0 && M!=0) {
        vector<long long> p;

        long long ans=0;

        for(int i=0; i<N; ++i) {
            long long temp;
            cin >> temp;
            p.push_back(temp);
            ans=MAX(ans,temp);
        }

        sort(p.begin(),p.end());

        for(int i=0; i<N; ++i) {
            for(int j=i; j<N; ++j) {
                if(p[i]+p[j]>M) break;
                p.push_back(p[i]+p[j]);
                ans=MAX(ans,p[i]+p[j]);
            }
        }

        sort(p.begin(),p.end());

        for(int i=0; i<(int)p.size(); ++i) {
            auto itr=upper_bound(p.begin(),p.end(),M-p[i]);
            if(itr==p.begin()) break;
            else --itr;
            ans=MAX(ans,p[i]+*itr);
        }

        cout << ans << endl;
        cin >> N >> M;
        p.clear();
    }
    return 0;
}

C++: #include<iostream>
#include<set>
#include<vector>
using namespace std;
typedef unsigned int uint;
uint maxv;
void solve(uint now,uint m,uint *a,int n){
  int r=n-1,l=0,mid;
  while(l <=r){
    mid = (l+r)/2;
    if ( a[mid]+now>m)r=mid-1;
    else if ( a[mid]+now <m)l=mid+1;
    else break;

  }
  if ( now+a[mid]>maxv&& now+a[mid]<m)maxv=now+a[mid];
}


main(){
  int n;
  uint m;
  while(scanf("%d%d",&n,&m) && n){
    set<uint> S;    
    uint one[n];
    uint two[n*n];
    int p=0;
    for(int i=0;i<n;i++)scanf("%d",&one[i]);
    for(int i=0;i<n;i++){
      for(int j=i;j<n;j++){
	if ( S.find(i+j) == S.end())S.insert(i+j),two[p++]=one[i]+one[j];
      }
    }
    sort(one,one+n);
    sort(two,two+p);
    maxv=0;
    for(int i=0;i<p;i++){
      if ( two[i]+one[0]>m)break;
      if ( two[i]+two[0]<=m)solve(two[i],m,two,p);
      if ( two[i]+one[0]<=m)solve(two[i],m,one,n);
    }
    printf("%d\n",maxv);
  }
  return false;
}