mirror of
https://github.com/Brandon-Rozek/website.git
synced 2024-09-19 22:25:12 -04:00
16 lines
798 B
Markdown
16 lines
798 B
Markdown
|
# Strings
|
||
|
|
|
||
|
|
## Character Codes
|
||
|
|
|
||
|
|
Character codes are mappings between numbers and symbols which make up a particular alphabet.
|
||
|
|
|
||
|
|
The *American Standard Code for Information Interchange* (ASCII) is a single-byte character code where $2^7 = 128$ characters are specified.
|
||
|
|
|
||
|
|
Symbol assignments were not done at random. Several interesting properties of the design make programming tasks easier:
|
||
|
|
|
||
|
|
- All non-printable characters have either the first three bits as zero or all seven lowest bits as one. This makes it easy to eliminate them before displaying junk.
|
||
|
|
- Both the upper and lower case letters and the numerical digits appear sequentially
|
||
|
|
- We can get the numeric order of a letter by subtracting the first letter
|
||
|
|
- We can convert a character from uppercase to lowercase by $Letter - "A" + "a"$
|
||
|
|
|