Maximum White Tiles Covered by a Carpet.js

// Runtime: 267 ms (Top 75.00%) | Memory: 62.7 MB (Top 77.27%)
/**
 * @param {number[][]} tiles
 * @param {number} carpetLen
 * @return {number}
 */
var maximumWhiteTiles = function(tiles, carpetLen) {
    const sorted = tiles.sort((a, b) => a[0]-b[0])
    let res = 0

    let total = 0
    let right = 0

    for (let tile of sorted){
        const start = tile[0]
        const end = start + carpetLen - 1
        while(right < sorted.length && tiles[right][1] < end){
            total += tiles[right][1] - tiles[right][0] + 1
            right+=1
        }
        if(right === sorted.length || sorted[right][0] > end){
            res = Math.max(res, total)
        } else{
            res = Math.max(res, total + (end-tiles[right][0] + 1))
        }
        total -= tile[1] - tile[0] + 1
    }

    return res
};