386.js

/** ------------------------------------------------------------------------------
 * 
 * 386. Lexicographical Numbers
 * Topics: DFS
 * https://leetcode.com/problems/lexicographical-numbers/description/
 * 
 ------------------------------------------------------------------------------ */
/**
 * @param {number} n
 * @return {number[]}
 * 이게되네
 */
var lexicalOrder = function (n) {
  const array = Array.from({ length: n }, () => 0)

  for (let i = 1; i <= n; i++) {
    array[i - 1] = i
  }

  return array.sort((a, b) => a.toString().localeCompare(b.toString()))
}

/**
 * dfs 풀이
 */
var lexicalOrder = function (n) {
  const arr = []

  const dfs = (num, n) => {
    if (num > n) return

    arr.push(num)

    for (let i = 0; i <= 9; i++) {
      dfs(num * 10 + i, n)
    }
  }

  for (let i = 1; i <= 9; i++) {
    dfs(i, n)
  }

  return arr
}

/**
 * 다른 풀이
 */
var lexicalOrder = function (n) {
  let output = []
  let currentNumber = 1

  for (let i = 0; i < n; i++) {
    output.push(currentNumber)

    if (currentNumber * 10 <= n) {
      currentNumber *= 10
    } else {
      if (currentNumber >= n) {
        currentNumber = Math.floor(currentNumber / 10)
      }
      currentNumber += 1

      while (currentNumber % 10 === 0) {
        currentNumber = Math.floor(currentNumber / 10)
      }
    }
  }

  return output
}

console.log(lexicalOrder(13))