Financial Management

Problem Description

Larry graduated this year and found a job. He makes a lot of money, but somehow it never seems to be enough. Larry believes he needs to manage his investments to solve his financial problems. Larry has obtained the detailed statement of his bank account and wants to see how much money he has. Please help Larry write a program that computes the average balance from the month-end balances over the past 12 months.

Input Format

The input contains 12 lines, each holding one number, the balance of a certain month. Every number is a positive number not exceeding 1,000,000, kept to two decimal places, with the $ sign omitted.

Output Format

Output one number: the average month-end balance over these 12 months, rounded to two decimal places, prefixed with a $ sign.

Sample Input

100.00
489.12
12454.12
1234.10
823.05
109.20
5.27
1542.25
839.18
83.99
1295.01
1.75

Sample Output

$1581.42