LuckyCounter | Topcoder Archive

Problem Statement

Suppose that we're given a moment of time written as HH:MM, where HH is the hour and MM is the minutes. Let's say that this moment is lucky if it is formatted AB:AB, AA:BB or AB:BA, where both occurrences of A stand for the same digit and both occurrences of B also stand for the same digit. It is allowed for the digits represented by A and B to be the same as well.

You are given a String[] moments, where each element represents a single moment of time. Return how many of these time moments are lucky.

Definition

Class:: LuckyCounter
Method:: countLuckyMoments
Parameters:: String[]
Returns:: int
Method signature:: int countLuckyMoments(String[] moments)
(be sure your method is public)

Constraints

moments will contain between 1 and 50 elements, inclusive.
Each element of moments will be formatted "HH:MM" (quotes for clarity), where HH is between 00 and 23, inclusive, and MM is between 00 and 59, inclusive.

Examples

```
{"12:21", "11:10"}
```
```
Returns: 1
```
12:21 is lucky, while 11:10 is not.
```
{"00:00", "00:59", "23:00"}
```
```
Returns: 1
```
Only 00:00 is lucky here (note that it is formatted AB:AB, AA:BB and AB:BA at the same time).
```
{"12:34"}
```
```
Returns: 0
```

{"12:11", "22:22", "00:01", "03:30", "15:15", "16:00"}

Returns: 3

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