2048. Next Greater Numerically Balanced Number

Problem Link

Description

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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 <= 106

Solution

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Python3

class Solution:
    def nextBeautifulNumber(self, n: int) -> int:
        
        def good(counter):
            for k, v in counter.items():
                if int(k) != v:
                    return False
            
            return True
        
        n += 1
        counter = collections.Counter(str(n))
        
        while not good(counter):
            n += 1
            counter = collections.Counter(str(n))
        
        return n