Problem A
Not Amused

Ordinarily, when you got to an amusement park, you pay for your ticket, you ride as many rides as you like and then you leave at the end of the day. If you leave early or get there late you don’t get a discount. Bob’s Pretty Safe Playland is ramping up a new plan to help attract more customers; you pay in proportion to the amount of time you spend in the park. Although Bob expects to lose some money on customers who just stop by for a couple of rides, he expects to make it back on the people who end up staying for a long time.

Under Bob’s new pricing scheme, customers pay $\$ 0.10$ for each minute they spend in the park. Bob will send a bill after a few days, and customers can can pay at their convenience. Bob will use a computer system to manage billing. It will notice when each customer enters and leaves. For each day, it will generate a report of how much each customer owes. Your job is to write that program.


Input consists of logs for up to $20$ days. The log for a given day starts with the word “OPEN” and ends with the word “CLOSE”. Between these entries are lines describing when various customers enter and leave the park. When a customer enters the park, it is recorded with a line like “ENTER Timmy 25”. This indicates that Timmy entered the park $25$ minutes after it opened. When a customer leaves the park, it is recorded like: “EXIT Timmy 130”. This indicates that Timmy left the park $130$ minutes after it opened. In this case, Timmy spent $105$ minutes in the park.

All distinct customers have different names consisting of $1$ to $20$ lower or uppercase (a-z) characters. At most $20$ different customers visit the park during a day. Entry and exit times are all in the range $[0,800]$. Log entries for each day are sorted by minute. The logging system is foolproof in that each enter has a matching exit some time later the same day. There are no ENTER reports for a customer who is already in the park, and there are no EXIT reports for a customer who was not previously in the park. At the start and the end of each day, the park is empty of customers.


For each day, print out a report like the following. Give the total bill for each customer. Sort your report alphabetically by customer name and leave a blank line between reports for consecutive days.

Sample Input 1 Sample Output 1
ENTER Alice 15
EXIT Sam 20
EXIT Alice 700
ENTER Alice 10
EXIT Sam 20
EXIT Alice 35
ENTER Sam 700
EXIT Sam 710
Day 1
Alice $68.50
Sam $2.00

Day 2
Alice $2.50
Sam $2.50

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