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

while (line = lines.shift()) {
	const [n, max] = line.split(' ').map(Number);
	if (n === 0 && max === 0) {break;}
	let prices = lines.shift().split(' ').map(Number);
	let maxPrice = 0;

	for (let i = 0; i < n; i++) {
		for (let j = 0; j < n; j++) {
			if (i === j) continue;

			var sum = prices[i] + prices[j]; 
			if (sum > max) continue;
			maxPrice = Math.max(maxPrice, sum);
		}
	}

	console.log(maxPrice === 0 ? 'NONE': maxPrice);
}
