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The three-letter mnemonic can be used to group similar coding practices and to indicate to which category a coding practice belongs to.
The numeric value is used to give each coding practice a unique identifier. Numeric values in the range of 00 to 49 are reserved for recommendations, and values in the range of 50 to 99 are reserved for rules. (The values used for the CERT C coding standard are different. It uses 00-29 for recommendations and 30-99 for rules.) Rules and recommendations are frequently referenced from the guidelines in this standard by their identifier and title.
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