# Regex to Match Dollar Amounts with Optional Cents

Problem: How to match dollar amounts in a given string? If cent amounts are given, those should match as well.

Solution: You can use regular expression pattern `'(\\$[0-9]+(.[0-9]+)?)'` to find all numbers that start with a dollar symbol, followed by an arbitrary number of numerical digits, followed by an optional decimal point and an arbitrary number of numerical digits.

Here’s the code:

```import re

report = '''
If you invested \$1 in the year 1801, you would have \$18087791.41 today.
This is a 7.967% return on investment.
But if you invested only \$0.25 in 1801, you would end up with \$4521947.8525.
'''

dollars = [x for x in re.findall('(\\$[0-9]+(\.[0-9]+)?)', report)]

print(dollars)
```

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