Some scripts you will write for cybersecurity encryption and decryption will need to access each character in a string. As a warmup for this, let's try a script that checks and displays a certain character in a string.
Example script: char_access_intro
- Enter this script and save it as char_access_intro.
- Flash the script into the micro:bit.
# char_access_intro from microbit import * sleep(1000) s = "ABCDEF 12345" print("Fifth character in s:") c = s print("c = s =", c) print()
- Open the terminal.
- Verify that it displays c = s = F.
- Try replacing 5 with other values, like 0, 1, 2, ...and anything up to 11. What happens with each value?
How It Works
The string s is "ABCDEF 12345". The string name, followed by a positive index value in square brackets, returns the character at that location in the string. The index starts with A at s, B is at s, and so on up to the character 5 at s. You can also use -1 through -12 to index characters from rightmost to left.
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