Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func main() {
	io := NewIo()
	defer io.Flush()
	for {
		n, m := io.NextInt(), io.NextInt()
		if n == 0 {
			break
		}
		a := make([]int, n)
		for i := 0; i < n; i++ {
			a[i] = io.NextInt()
		}
		ans := 0
		for i := 0; i < n; i++ {
			for j := i + 1; j < n; j++ {
				if a[i]+a[j] <= m {
					ans = intMax(a[i]+a[j], ans)
				}
			}
		}
		if ans == 0 {
			io.Println("NONE")
		} else {
			io.Println(ans)
		}
	}
}

func intMax(a, b int) int {
	if a < b {
		return b
	}
	return a
}

// I/O template
type Io struct {
	reader    *bufio.Reader
	writer    *bufio.Writer
	tokens    []string
	nextToken int
}

func NewIo() *Io {
	return &Io{
		reader: bufio.NewReader(os.Stdin),
		writer: bufio.NewWriter(os.Stdout),
	}
}

func (io *Io) Flush() {
	err := io.writer.Flush()
	if err != nil {
		panic(err)
	}
}

func (io *Io) NextLine() string {
	var buff []byte
	for {
		line, isPrefix, err := io.reader.ReadLine()
		if err != nil {
			panic(err)
		}
		buff = append(buff, line...)
		if !isPrefix {
			break
		}
	}
	return string(buff)
}

func (io *Io) Next() string {
	for io.nextToken >= len(io.tokens) {
		line := io.NextLine()
		io.tokens = strings.Fields(line)
		io.nextToken = 0
	}
	s := io.tokens[io.nextToken]
	io.nextToken++
	return s
}

func (io *Io) NextInt() int {
	i, err := strconv.Atoi(io.Next())
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) NextFloat() float64 {
	i, err := strconv.ParseFloat(io.Next(), 64)
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) Println(a ...interface{}) {
	fmt.Fprintln(io.writer, a...)
}

func (io *Io) Printf(format string, a ...interface{}) {
	fmt.Fprintf(io.writer, format, a...)
}

func (io *Io) PrintIntSlice(a []int) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func (io *Io) PrintStringSlice(a []string) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func Log(name string, value interface{}) {
	fmt.Fprintf(os.Stderr, "%s=%+v\n", name, value)
}

func ExampleIo() {
	io := NewIo()
	defer io.Flush()
	a := make([]int, 0, 3)
	a[0], a[1], a[2] = io.NextInt(), io.NextInt(), io.NextInt()
	io.Println(a)
	io.PrintIntSlice(a)
	Log("io", a)
}

C++: #include <bits/stdc++.h>
using namespace std;
int a[1000];
int main() {
  while (true) {
    int n, m; cin >> n >> m;
    if (n == 0 && m == 0)
    	break;
    for (int i = 0; i < n; i++)
    	cin >> a[i];
   	sort(a, a + n);
    int ans = 0;
    for (int i = 0; i < n; i++) {
      int p = lower_bound(a, a + n, a[i]) - a;
      if (a[i] + a[p] > m)
        p--;
      if (i == p)
        p--;
      if (p < 0) continue;
      if (a[i] + a[p] > ans)
        ans = a[i] + a[p];
    }
    if (ans)
    	cout << ans << endl;
    else
    	cout << "NONE" << endl;
  }
}

C++: //QWsin
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#define rep(i,x,y) for(int i=x;i<=y;++i)
using namespace std;

const int maxn=1000+10;

int a[maxn];

int main()
{
	int n,m;
	while(1)
	{
		cin>>n>>m;
		if(!n && !m) break;
		rep(i,1,n) scanf("%d",a+i);
		sort(a+1,a+n+1);
		
		int ans=0;
		for(int i=n;i>=2;--i)
		{
			int p=m-a[i];
			int pos=upper_bound(a+1,a+i,p)-a;
			if(pos==i) --pos;
			if(a[pos]+a[i] <= m) ans=max(ans,a[pos]+a[i]);
			--pos;if(pos==0) continue;
			if(a[pos]+a[i] <= m) ans=max(ans,a[pos]+a[i]);
		}
		if(ans==0) puts("NONE");
		else cout<<ans<<endl;
	}
	return 0;
}

C++: #define NOMINMAX
#define TEST_MODE true

#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES

#include "bits/stdc++.h"
#include <random>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
#define rep2(i, a, b) for (int i = (a); i < (int)(b); ++i)
#define rrep(i, n) for (int i = (n)-1; i >= 0; --i)
#define rrep2(i, a, b) for (int i = (a)-1; i >= (int)b; --i)
#define range(i, a, b, c) for (int i = a;             \
                                   c > 0 ? i < b : i > b; \
                                   i += c)
#define chmax(a, b) (a = (a) < (b) ? (b) : (a))
#define chmin(a, b) (a = (a) > (b) ? (b) : (a))
using ll = long long;
using ull = unsigned long long;
using ld = long double;
#define all(a) begin(a), end(a)
#define ifnot(a) if (not(a))
#define int long long

#ifdef LOCAL_ENV

#if TEST_MODE == true
const bool test = true;
#define dump(x) cerr << #x << " : " << (x) << " "
#define dumpl(x) dump(x) << endl
#else
const bool test = false;
#define dump(x) 
#define dumpl(x)
#endif

#else
const bool test = false;
#define dump(x) 
#define dumpl(x)
#endif

int dx[] = { 1, 0, -1, 0 };
int dy[] = { 0, 1, 0, -1 };
const int inf = (int)1 << 60;
const int undefined = inf;
const ll INFL = (ll)1 << 60;
ll mod_n = (int)1e9 + 7;
const double eps = 1e-10;
typedef long double Real;
// return -1, 0, 1
int sgn(const Real &r) { return (r > eps) - (r < -eps); }
int sgn(const Real &a, const Real &b) { return sgn(a - b); }

//.....................
const int MAX = (int)2e5 + 5;

vector<string> split(const string &str, char sep)
{
	vector<string> v;
	stringstream ss(str);
	string buffer;
	while (getline(ss, buffer, sep))
	{
		v.push_back(buffer);
	}
	return v;
}

string join(const vector<string>& v, const string delim = 0) {
	string s;
	if (!v.empty()) {
		s += v[0];
		for (decltype(v.size()) i = 1, c = v.size(); i < c; ++i) {
			if (delim != "") s += delim;
			s += v[i];
		}
	}
	return s;
}

string operator * (const string& s, const int& n) {
	string res = "";
	rep(i, n) res += s;
	return res;
}

template <class InputIterator>
int sum(InputIterator begin, InputIterator end)
{
	return accumulate(begin, end, 0ll);
}

template<typename T>
T gcd(T a, T b)
{
	if (a == inf) return b;
	if (b == inf) return a;
	T c;
	while (a != 0) {
		c = a; a = b % a;  b = c;
	}
	return b;
}

template<typename T>
T bit_count(T N) {
	T cnt = 0;
	while (N) {
		if (N & 1) cnt++;
		N >>= 1;
	}
	return cnt;
}

template<typename T>
void print_vec(ostream& ostream, vector<T> a) {
	rep(i, a.size() - 1) ostream << a[i] << " ";
	ostream << a.back() << endl;
}

ll pow_n(ll x, ll n) {
	ll res = 1;
	while (n > 0) {
		if (n & 1) res = res * x;
		x = x * x;
		n >>= 1;
	}
	return res;
}

template<class T, class U>
T mod_pow(T x, U n) {
	T res = 1;
	while (n > 0) {
		if (n & 1) res = res * x;
		x = x * x;
		x %= mod_n;
		n >>= 1;
		res %= mod_n;
	}
	return res;
}

template<class T>
T mod_rev(T a) {
	T res = 1;
	return mod_pow(a, mod_n - 2);
}

int H, W;

bool grid_ng(int y, int x) {
	return y < 0 || y >= H || x < 0 || x >= W;
}

struct Point {
	int x, y;
	Point(int y_, int x_) : y(y_), x(x_) {}
	bool operator < (const Point& r) const {
		if (y != r.y) return y < r.y;
		return x < r.x;
	}
};

struct Vertex {
	int id, dist;
	bool operator > (const Vertex& r) const {
		return dist > r.dist;
	}
};

struct Edge {
	int to, weight;
	Edge(int to, int weight) : to(to), weight(weight) {}
};

using Graph = vector<vector<Edge>>;
Graph g;

int n, m;
int a, b, c;

class Solver {
public:
	vector<int> a;
	int ans() {
	}

	void solve() {
		cin >> n >> m;
		if (n == 0) exit(0);
		a.resize(n);
		rep(i, n) cin >> a[i];

		sort(all(a));
		int cnt = 0;
		int res = 0;

		rep(i, n) rep(j, n) {
			if (i == j) continue;
			int b = a[i] + a[j];
			if (b > m) continue;
			chmax(res, b);
		}
		cout << (res != 0 ? to_string(res) : "NONE") << endl;
	}
};

signed main()
{
	srand((unsigned int)time(NULL));
	cout << fixed << setprecision(20);
	//auto ptr = new Solver();
	//ptr->solve();
	//delete ptr;

	while(true) {
		auto ptr = new Solver();
		ptr->solve();
		delete ptr;
	}
	//while (true) {
	//	if (cin.eof() == true) break;
	//	auto ptr = new Solver();
	//	ptr->solve();
	//	delete ptr;
	//}
	return 0;
}