Manage Names

You are given a series of commands to manage a list of names. Each command is either add name or remove name. The add name command adds the specified name into the list (if it is not already present), while the remove name command removes the name if it exists in the list.

After processing all commands, you are required to output the final list of names in ascending order. The rules for the operations can be summarized as follows:

• \(\text{add: insert the name if not present}\)
• \(\text{remove: delete the name if it exists}\)

Note that the names are case-sensitive and are given in lower-case only.

inputFormat

The input begins with a single integer \(N\) (\(0 \leq N \leq 1000\)) representing the number of commands. Each of the following \(N\) lines contains one command in the form of either add name or remove name.

outputFormat

Output the final sorted list of names, each on a new line. If no names remain after processing all commands, output nothing.

## sample

6
add alice
add bob
add charlie
remove bob
add dave
remove bob

alice
charlie
dave

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