Thanks for this, I found it helpful. But the English could be improved.
I improved the language quality. Mostly grammar, but also changed some wording choices that felt unnatural. Also did some very minor formatting.
I removed the Redis paragraph because I couldn't really make sense of it. Perhaps @labuladong can clarify?
(I feel a need to preface this by saying that the changes I made were based solely on the English version, and the reading experience, for I do not speak Chinese (I'm not even sure if it's Mandarin, Cantonese or which one, nor if there's any difference in writing). Should you object to any changes, please let me know)
1. Changed the apostrophe character from *`* to *'*. The former is not used as an apostrophe, and is actually an accent mark (for preferred characters, refer to (this)[http://snowball.tartarus.org/texts/apostrophe.html] (U+0027 ', U+2019 ’, U+201B ‛)).
2. Changed certain verb forms. For instance: *"The last question is that **writing** a function to calculate [...]"* to *"The last question is **to write** a function which calculates [...]"* (also *which* -> *to* in order to avoid the repetition).
3. Changed the capitalization where necessary. For example: *Helpless* to *helpless* (since it's not a proper name); *We* to *we* (middle of a sentence).
4. Changed a few verbs to nouns, and vice versa: *"explain"* (on its own serves as an imperative, which would demand that the reader explain it) to *"explanation"*; *"storage"* to "store [the least editing distance of s1 and s2; L226]".
5. Fixed redundant spaces: *"[...] `s2` in [...]"* to *"[...] `s2` in [...]"*; *"s1[i]！=s2[j]"* to *"s1[i] != s2[j]"*
6. Changed a few odd phrases: *"a violent solution"* to *"a brute force solution"* ( (most)[https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwiolLjsxK3xAhUspIsKHU-9BwEQFjADegQIBBAD&url=https%3A%2F%2Fgsdrc.org%2Fwp-content%2Fuploads%2F2019%2F11%2F671_P-CVE_Programming_on_Men_Women_Boys_and_Girls.pdf&usg=AOvVaw2QjJ_-yjxxw2oWYtG77sgE], albeit (not all)[https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwiolLjsxK3xAhUspIsKHU-9BwEQFjABegQIAhAE&url=https%3A%2F%2Fwww.programmersought.com%2Farticle%2F27011223160%2F&usg=AOvVaw1f6OCbf1r7M8GAfmGotBDg], uses of the former did not refer to programming ); *"from the bottom to up"* to *"from the bottom up"* (or *"bottom-up"*; see: (from the bottom up)[https://www.lexico.com/definition/from_the_bottom_up], and (bottom-up)[https://dictionary.cambridge.org/dictionary/english/bottom-up] ); *"operation number"* to *"the number of operations"* (this one might have been more subjective).
7. Removed latex dollar signs (since github markdown does not support it): *"$O(min(M, N))$"* to *"O(min(M, N))"* (as used in other articles).
8. Pluralized certain nouns after *"any"* ( ("We use any for indefinite quantities in questions and negative sentences")[https://dictionary.cambridge.org/grammar/british-grammar/any] ): *"any operation"* to *"any operations"*.
9. Added some formatting: "dp(i, j)" to "`dp(i, j)`" (L98).
I'm also not sure if *"[...] I wrote some words out of place by mistake"* refers to mistyping, but it's still more than clear, albeit slightly wordy.
To reiterate, should any of these be of concern, let me know, especially since it is my second language.
Best regards
