60 lines
1.6 KiB
Markdown
60 lines
1.6 KiB
Markdown
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# Spam Masker Challenge Tips
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## Rules:
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* You shouldn't use a standard library function.
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* You should only solve the challenge by manipulating the bytes directly.
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* Manipulate the bytes of a string using indexing, slicing, appending etc.
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* Be efficient: Do not use string concat (+ operator).
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* Instead, create a new byte slice as a buffer from the given string argument.
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* Then, manipulate it during your program.
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* And, for once, print that buffer.
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* Mask only links starting with `http://`
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* Don't check for uppercase/lowercase letters
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* The goal is learning how to manipulate bytes in strings, it's not about creating the perfect masker.
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* For example: A spammer can prevent the masker like this (for now this is OK):
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```
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"Here's my spammy page: hTTp://youth-elixir.com"
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^^
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```
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* But, you should catch this:
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```
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INPUT:
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Here's my spammy page: http://hehefouls.netHAHAHA see you.
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OUTPUT:
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Here's my spammy page: http://******************* see you.
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```
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## Steps:
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1. Check whether there's a command line argument or not. If not, quit from the program with a message.
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2. Create a byte buffer as big as the argument.
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3. Loop and detect the `http://` patterns
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4. Copy the input character by character to the buffer
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5. If you detect `http://` pattern, copy the `http://` first, then copy the `*`s instead of the original link until you see whitespace character.
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For example:
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```
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INPUT:
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Here: http://www.mylink.com Click!
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OUTPUT:
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Here: http://************** Click!
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```
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6. Print the buffer as a string
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