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Q&A Tips for golfing in Python

Replace n+1 with -~n and n-1 with ~-n For integers, n+1 and ~-n have the same value, as have n-1 and -~n. While the expressions themselves have the same lengths, the replacements often allow to s...

posted 2y ago by celtschk‭  ·  edited 2y ago by celtschk‭

Answer
#2: Post edited by user avatar celtschk‭ · 2021-09-16T05:44:23Z (over 2 years ago)
  • # Replace `n+1` with `-~n` and `n-1` with `~-n`
  • For integers, `n+1` and `~-n` have the same value, as have `n-1` and `-~n`.
  • While the expressions themselves have the same lengths, the replacements often allow to save space by allowing either to remove whitespace or omit parentheses due to different precedence.
  • For example,
  • ```
  • a=12*(n+1)
  • ```
  • can be replaced by
  • ```
  • a=12*-~n
  • ```
  • # Replace `n+1` with `-~n` and `n-1` with `~-n`
  • For integers, `n+1` and `~-n` have the same value, as have `n-1` and `-~n`.
  • While the expressions themselves have the same lengths, the replacements often allow to save space by allowing either to remove whitespace or to omit parentheses due to different precedence.
  • For example,
  • ```
  • a=12*(n+1)
  • ```
  • can be replaced by
  • ```
  • a=12*-~n
  • ```
#1: Initial revision by user avatar celtschk‭ · 2021-09-16T05:43:23Z (over 2 years ago)
# Replace `n+1` with `-~n` and `n-1` with `~-n`

For integers, `n+1` and `~-n` have the same value, as have `n-1` and `-~n`.

While the expressions themselves have the same lengths, the replacements often allow to save space by allowing either to remove whitespace or omit parentheses due to different precedence.

For example,
```
a=12*(n+1)
```
can be replaced by
```
a=12*-~n
```