Remove Duplicate File Paths

You are given a list of file paths represented as strings. Your task is to remove any duplicate file paths while preserving the order of their first occurrence.

Input Format: The first line contains an integer n representing the number of file paths. Each of the following n lines contains a file path.

Output Format: Print the unique file paths, each on a new line, in the order of their first occurrence.

Example:

Input:
6
root.a
root.b
root.a
root.c.d
root.c.e
root.c.d
Output:
root.a
root.b
root.c.d
root.c.e

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The solution should employ an algorithm with a time complexity of \(O(n)\) on average, where \(n\) is the number of file paths.

inputFormat

The input is from stdin. The first line contains an integer n indicating the number of file paths. The following n lines each contain one file path string.

outputFormat

The output should be written to stdout. Print the unique file paths (one per line) in the order of their first appearance.

## sample

6
root.a
root.b
root.a
root.c.d
root.c.e
root.c.d

root.a
root.b
root.c.d
root.c.e

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