Calculate Total Revenue

You are given sales records for various product categories. Each record contains three fields: an ID, a category name, and a sale amount. Your task is to compute the total revenue for each category and output them sorted in lexicographical order. The total revenue for each category is the sum of all sale amounts (rounded to two decimal places).

In mathematical terms, for each category \( C \), compute:
\( \text{total}_C = \sum_{i \in C} \text{amount}_i \)
and output the result as category: total where total is formatted to two decimals.

inputFormat

The first line contains a non-negative integer \( n \) indicating the number of sales records.

Each of the following \( n \) lines contains a sales record in the following format:
ID, category, amount
where the fields are separated by a comma and a space. The ID is an integer, category is a string, and amount is a decimal number.

outputFormat

For each category that appears in the input, output one line in the following format:
category: total
where total is the sum of all sale amounts for that category rounded to two decimal places. The output lines must be sorted in lexicographical order by the category name.

5
1, electronics, 200.00
2, groceries, 50.00
3, electronics, 100.00
4, clothing, 150.00
5, groceries, 100.00

clothing: 150.00
electronics: 300.00
groceries: 150.00