const input = require('fs').readFileSync('/dev/stdin', 'utf8');
const lines = input.trim().split('\n');

let array;
let index = 0;
let n;
let m;
let answers = [];
while (line = lines.shift()) {
    if(index === 0){
        const test = line.split(' ').map(Number);
        n = test[0];
        m = test[1];
        index ++;
    } else {
        array = line.split(' ').map(Number);


        let answer = 0;
        for(let i = 0; i<n ;i++){
            for(let j = 0;j<n;j++){
                if(i === j){
                    continue;
                }
                const test = array [i] + array [j];
                if(test > answer && test <= m){
                    answer = test;
                }
            }
        }
        index = 0;
        answers.push(answer);

    }
}
/*
let answer = 0;

for(let i = 0; i<n ;i++){
    for(let j = 0;j<n;j++){
        if(i === j){
            continue;
        }
        const test = array [i] + array [j];
        if(test > answer && test <= m){
            answer = test;
        }
    }
}
*/
answers.forEach(data => console.log(data ? data : 'NONE'))
// console.log(answers);
