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The task at hand is to determine the winning number in a unique lottery system designed for Martian inhabitants. The game works by participants betting on numbers from a specific range, and the winner is the first to bet on a unique number not previously chosen.

Input and Output

Each test case consists of a line starting with an integer N (≤ 10^5), followed by N bets. These bets are separated by spaces. The output should be the winning number only if there is one. If no unique number exists after all bets, return "None".

Example 1

Input:

7 5 31 5 88 67 88 17The program processes each bet, keeping track of each number. The first unique number is "31", so it is printed.

Output:

31

Example 2

Input:

5 888 666 666 888 888In this case, the bets go 5 times. The program counts occurrences: 888 appears 3 times, 666 appears 2 times, and both have duplicates. Thus, no unique winner exists, and the output is "None".

Technology in Action

The provided C++ implementation uses an efficient array-based approach to track bets:

Read the number of bets and store each in an array.

Maintain a frequency array to count occurrences.

After processing all bets, iterate through the frequency array to find the first count that equals 1.

Output this number or "None" if no unique number exists.

This approach ensures that the solution is both simple and efficient, handling up to the maximum constraints smoothly.

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