# Calculator

#misc

- [Calculator](#calculator)
- [Decoding Tabs and Spaces](#decoding-tabs-and-spaces)
- [Raw tabs and spaces](#raw-tabs-and-spaces)

There is a suspiciously large whitespace at the bottom of the file. Opening the file in VS Code we can see that the whitespace is made up of a combination of spaces and tabs, indicated by `.` for a space and `->` for a tab.


I copied over the spaces and tabs into a separate file.

At first the format looked like morse code so I wrote a Python script to replace each space with a `.` and tab with a `-`, but the resulting morse code was invalid.

Another approach I thought of was to convert them to binary instead, since we only have two unique characters.

## Decoding Tabs and Spaces

```py
with open("tabs_and_spaces.txt", 'r') as f:
content = f.readlines()

flag = ''

for word in content:
binary = ''
for char in word:
if char == ' ':
binary += '0'
elif char == '\t':
binary += '1'
elif char == '\n':
binary += ' '

ascii_code = int(binary, 2)

# Do not append Start of Header (SOH) character
flag += chr(ascii_code) if ascii_code > 1 else ''

print("Flag:", flag)
```

### Raw tabs and spaces

Each element represent a line
```py
[' \t \t\t\n', '\t\n', ' \t \t \t\n', '\t\n', ' \t \t \t \n', '\t\n', ' \t\t\t\t \t\t\n', '\t\n', ' \t\t \t \n', '\t\n', ' \t\t \t\t \n', '\t\n', ' \t\t\t \t \n', '\t\n', ' \t\t \t \n', '\t\n', ' \t\t \t \n', '\t\n', ' \t \t \t \n', '\t\n', ' \t\t \n', '\t\n', ' \t\t \t \n', '\t\n', ' \t\t \t\n', '\t\n', ' \t\t \t \t\n', '\t\n', ' \t \t\t \n', '\t\n', ' \t\t \t \n', '\t\n', ' \t\t\t\t\t \t\n', '\t\n', ' ']
```

Including the SOH character (ASCII code 1) will insert a default glyph in between each character like this:

```
C☺I☺T☺{☺h☺f☺t☺4☺b☺T☺0☺4☺1☺5☺L☺b☺}☺`
```

**Flag:** `Flag: CIT{hft4bT0415Lb}`