Avoid the use of numerical values or "magic numbers" (constant values that represent an arbitrary value, such as a determined appropriate buffer size, or a malleable concept such as the age a person is considered an adult, which could change in code when a different country) in code where it is possible. Rather, use appropriately named symbolic constants clarify the intent of the code. In addition, if a specific value needs to be changed reassigning a symbolic constant once is more efficient and less error prone then replacing every instance of the value to be changed.
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