2048. Next Greater Numerically Balanced Number

Medium

題目描述

Description

An integer x is numerically balanced if for every digit d in the number x, there are exactly d occurrences of that digit in x.

Given an integer n, return the smallest numerically balanced number strictly greater than n.

Example 1:

Input: n = 1
Output: 22
Explanation:
22 is numerically balanced since:

• The digit 2 occurs 2 times.
  It is also the smallest numerically balanced number strictly greater than 1.

Example 2:

Input: n = 1000
Output: 1333
Explanation:
1333 is numerically balanced since:

• The digit 1 occurs 1 time.
• The digit 3 occurs 3 times. It is also the smallest numerically balanced number strictly greater than 1000. Note that 1022 cannot be the answer because 0 appeared more than 0 times.

Example 3:

Input: n = 3000
Output: 3133
Explanation:
3133 is numerically balanced since:

• The digit 1 occurs 1 time.
• The digit 3 occurs 3 times.
  It is also the smallest numerically balanced number strictly greater than 3000.

Constraints:

• 0 <= n <= $10^6$

解答

Solution

/**
 * @param {number} n
 * @return {number}
 */
var nextBeautifulNumber = function (n) {
  const beautifulNumbers = [
    1, 22, 122, 212, 221, 333, 1333, 3133, 3313, 3331, 4444, 14444, 22333,
    23233, 23323, 23332, 32233, 32323, 32332, 33223, 33232, 33322, 41444, 44144,
    44414, 44441, 55555, 122333, 123233, 123323, 123332, 132233, 132323, 132332,
    133223, 133232, 133322, 155555, 212333, 213233, 213323, 213332, 221333,
    223133, 223313, 223331, 224444, 231233, 231323, 231332, 232133, 232313,
    232331, 233123, 233132, 233213, 233231, 233312, 233321, 242444, 244244,
    244424, 244442, 312233, 312323, 312332, 313223, 313232, 313322, 321233,
    321323, 321332, 322133, 322313, 322331, 323123, 323132, 323213, 323231,
    323312, 323321, 331223, 331232, 331322, 332123, 332132, 332213, 332231,
    332312, 332321, 333122, 333212, 333221, 422444, 424244, 424424, 424442,
    442244, 442424, 442442, 444224, 444242, 444422, 515555, 551555, 555155,
    555515, 555551, 666666, 1224444,
  ];

  for (let i of beautifulNumbers) {
    if (i > n) {
      return i;
    }
  }
};

解題思路

Discussion 有個人貼了所有的 "beautiful" numbers 的清單
所以就用 for 迴圈找出最小且符合條件的數
對

for (let i of beautifulNumbers) {
  if (i > n) {
    return i;
  }
}

心得