Java

Building Strings Efficiently in Java

JavaStringsStringBuilderintermediate

Concatenating with + inside a loop allocates a new String each pass. StringBuilder mutates one buffer instead.

expected output

1,2,3

Why practise typing this

Typing strings code builds muscle memory for the symbols and indentation Java 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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