FavouriteDigits | Topcoder Archive

Problem Statement

Tetka Rapotacka just heard a juicy rumor about one of her neighbors: poor Jachym has lost N kacky (their local monetary unit) on a slot machine yesterday. Tetka Rapotacka now plans to share this rumor with everyone, including Tetka Klepetacka. Tetka Rapotacka has two favourite digits: digit1 and digit2. She only likes numbers that contain at least count1 occurrences of digit1 and at least count2 occurrences of digit2. When gossiping, she only uses numbers she likes. So if she does not like the number N, she will increase it until she finds a number that she likes.

You are given the long N and the four ints digit1, count1, digit2, and count2. Return the smallest integer that is greater than or equal to N, contains at least count1 occurrences of digit digit1, and at least count2 occurrences of digit digit2.

Definition

Class:: FavouriteDigits
Method:: findNext
Parameters:: long, int, int, int, int
Returns:: long
Method signature:: long findNext(long N, int digit1, int count1, int digit2, int count2)
(be sure your method is public)

Notes

The constraints guarantee that the return value will always fit into a long.

Constraints

N will be between 1 and 10^15 - 1, inclusive.
digit1 will be between 0 and 9, inclusive.
digit2 will be between 0 and 9, inclusive.
digit1 and digit2 will not be equal.
count1 will be at least 0.
count2 will be at least 0.
count1+count2 will be at most 15.

Examples

```
47
```
```
1
```
```
0
```
```
2
```
```
0
```
```
Returns: 47
```
As count1=0 and count2=0, Tetka Rapotacka likes all numbers.
```
47
```
```
5
```
```
0
```
```
9
```
```
1
```
```
Returns: 49
```
The number has to contain the digit 9. The next number that contains this digit is 49.
```
47
```
```
5
```
```
0
```
```
3
```
```
1
```
```
Returns: 53
```
```
47
```
```
2
```
```
1
```
```
0
```
```
2
```
```
Returns: 200
```
The correct return value may have more digits than N.

123456789012345

Returns: 123456789012422

```
92
```
```
1
```
```
1
```
```
0
```
```
0
```
```
Returns: 100
```

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