Next Greater Numerically Balanced Number

Tags : leetcode, cpp, medium

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.

Examples #

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 #

Solutions #

class Solution {
public:
    bool bt(int n){
        int d[10]={},x=n;
        while(x){d[x%10]++;x/=10;}
        for(int i=0;i<10;i++){if(d[i] and d[i]!=i) return false;}
        return true;
    }
    int nextBeautifulNumber(int n) {
        for(n++;!bt(n);n++);
        return n;
    }
};