Employee Salary Analysis

You are given data for a company’s employees. Each employee record has four fields: Name, Age, Department, and Salary. Some salaries may be missing and are indicated by the string NA.

Your task is to perform two steps:

1. Replace each missing salary with the overall average salary computed from the available (non-missing) salary entries. The overall average is computed over all employees with a provided salary.
2. Compute the average salary for each department. In this problem, the departments of interest are HR, Engineering, and Finance.

The averages must be output in the order: HR, Engineering, Finance. Each average should be printed on a new line and rounded to exactly 2 decimals.

Note: It is guaranteed that the input will include at least one record for each of the three departments.

inputFormat

The input is read from stdin and has the following format:

1. The first line contains an integer N representing the number of employees.
2. The next N lines each contain the details of one employee in the following order, separated by spaces:

Name Age Department Salary

Here, Salary is a number if available, or the string NA if the salary is missing.

outputFormat

The output is written to stdout and should consist of exactly three lines.

• The first line is the average salary of the HR department.
• The second line is the average salary of the Engineering department.
• The third line is the average salary of the Finance department.

Each average must be rounded to 2 decimals.

## sample

10
Alice 25 HR 50000
Bob 30 Engineering 60000
Charlie 45 Engineering 80000
David 35 HR 45000
Eva 28 Finance 52000
Frank 40 Engineering NA
Grace 50 Finance 65000
Hannah 23 HR 47000
Ian 33 Engineering 72000
Jack 41 Finance NA

47333.33
67718.75
58625.00

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