By default, all scalar variables with names beginning with I, J, K, L, M, or N are assumed to be default integer variables. Scalar variables with names beginning with any other letter are assumed to be default real variables. For example:
| Real Variables | Integer Variables | 
|---|---|
ALPHA
  |  JCOUNT   |  
BETA   |  ITEM_1
  |  
TOTAL_NUM   | 
NTOTAL   |  
Names beginning with a dollar sign ($) are implicitly INTEGER.
You can override the default data type implied in a name by specifying data type in either an IMPLICIT statement or a type declaration statement.
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