Employee Skill Management

You are given a series of operations to manage employees' skills. There are three types of operations:

• Type 1: Add a new skill to an employee. The operation is described as: 1 emp skill.
• Type 2: Remove a skill from an employee. The operation is described as: 2 emp skill.
• Type 3: Query and print all the skills of an employee in lexicographical order separated by a single space. If the employee has no skills, output None. The operation is described as: 3 emp.

For instance, if an employee has skills, the output should be sorted alphabetically. If not, output None.

The operations obey the following constraints:

• Let \( n \) be the number of operations.
• Each operation is provided in a single line via standard input.

Implement a solution that reads from standard input and writes the required output to standard output.

inputFormat

The first line contains an integer \( q \), the number of operations. Following this, there are \( q \) lines, each describing an operation in one of the following formats:

• For adding a skill: 1 emp skill
• For removing a skill: 2 emp skill
• For querying skills: 3 emp

Here, emp is the employee ID (an integer) and skill is a string without spaces.

outputFormat

For each query operation (type 3), output the employee's skills in lexicographical order separated by a single space on a new line. If an employee has no skills, output None (without quotes).

## sample

7
1 1 Coding
1 1 Design
1 2 Management
3 1
2 1 Design
3 1
3 2

Coding Design
Coding
Management

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