Python

Join Strings in Python

PythonPerformance & OptimizationString Concatadvanced

What this snippet does

Using join() is O(n) efficient, whereas repeated += concatenation in a loop is O(n^2) due to immutability.

Expected output

Hello World

Why practise typing this

Typing performance & optimization code builds muscle memory for the symbols and indentation Python uses most, which prose-based typing tests never cover. DevType measures your words per minute and accuracy on this snippet and tracks the individual characters you mistype, so later lessons can target them.

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