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This noncompliant code example shows a variable that is declared outside the for loop. This reduces reusability because the value of the loop index i will have changed after the for statement. Consider, for instance, the case when this code snippet is copied and pasted with the intent to use a different index j. If the index variable change is were omitted, the new loop would then attempt to iterate over index i. Unexpected behavior can follow because i remains in scope.
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Using a larger scope than what is necessary results in less reliable code.
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