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EX.+= is faster
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README.md
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README.md
@ -76,7 +76,7 @@ So, here we go...
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- [> Inpinity/无限 *](#-inpinity无限-)
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- [> Mangling time!修饰时间! *](#-mangling-time修饰时间-)
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- [Section: Miscellaneous](#section-miscellaneous)
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- [> `+=` is faster](#--is-faster)
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- [> `+=` is faster/更快的 `+=` ](#--is-faster更快的-)
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- [> Let's make a giant string!](#-lets-make-a-giant-string)
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- [> Explicit typecast of strings](#-explicit-typecast-of-strings)
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- [> Minor Ones](#-minor-ones)
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@ -2172,19 +2172,19 @@ True
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## Section: Miscellaneous
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### > `+=` is faster
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### > `+=` is faster/更快的 `+=`
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```py
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# using "+", three strings:
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# 用 "+" 连接三个字符串:
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>>> timeit.timeit("s1 = s1 + s2 + s3", setup="s1 = ' ' * 100000; s2 = ' ' * 100000; s3 = ' ' * 100000", number=100)
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0.25748300552368164
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# using "+=", three strings:
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# 用 "+=" 连接三个字符串:
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>>> timeit.timeit("s1 += s2 + s3", setup="s1 = ' ' * 100000; s2 = ' ' * 100000; s3 = ' ' * 100000", number=100)
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0.012188911437988281
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```
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#### 💡 Explanation:
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+ `+=` is faster than `+` for concatenating more than two strings because the first string (example, `s1` for `s1 += s2 + s3`) is not destroyed while calculating the complete string.
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#### 💡 说明:
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+ 连接两个以上的字符串时 `+=` 比 `+` 更快, 因为在计算过程中第一个字符串 (例如, `s1 += s2 + s3` 中的 `s1`) 不会被销毁.(译: 就是 `+=` 执行的是追加操作,少了一个销毁新建的动作.)
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---
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