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Signed-off-by: klausmelcher <[email protected]>

Author: klausmelcher

Labs/cbl/PAYROL00.cobol

@@ -1,25 +1,50 @@
-      *A   B
+      *         COBOL reference format (Figure 1., page 32)
+      *Columns:
+      *  1         2         3         4         5         6         7
+      *89012345678901234567890123456789012345678901234567890123456789012
+      *<A-><--------------------------B-------------------------------->
+      *Area                          Area
+      *<---Sequence Number Area                 Identification Area---->
+      *-----------------------
        IDENTIFICATION DIVISION.
+      *-----------------------
        PROGRAM-ID. PAYROL00.
+      *-------------
        DATA DIVISION.
+      *-------------
        WORKING-STORAGE SECTION.
       ****** Variables for the report
+      * level number
+      * |  variable name
+      * |  |          picture clause
+      * |  |          |
+      * V  V          V
        77  WHO        PIC X(15).
        77  WHERE      PIC X(20).
        77  WHY        PIC X(30).
        77  RATE       PIC 9(3).
        77  HOURS      PIC 9(3).
        77  GROSS-PAY  PIC 9(5).
 
+      * PIC X(15) -- fiftheen alphanumeric characters
+      * PIC 9(3)  -- three-digit value
+      *------------------
        PROCEDURE DIVISION.
+      *------------------
       ****** COBOL MOVE statements - Literal Text to Variables
            MOVE  "Captain COBOL" TO WHO.
            MOVE "San Jose, California" TO WHERE.
            MOVE "Learn to be a COBOL expert" TO WHY.
            MOVE 19 TO HOURS.
            MOVE 23 TO RATE.
+      * The string "Captain COBOL" only contains 13 characters,
+      * the remaining positions of variable WHO are filled with spaces
+      * The value 19 only needs 2 digits,
+      * the leftmost position of variable HOURS is filled with zero
       ****** Calculation using COMPUTE reserved word verb
            COMPUTE GROSS-PAY = HOURS * RATE.
+      * The result of the multiplication only needs 3 digits,
+      * the remaining leftmost positions are filled with zeroes
       ****** DISPLAY statements
            DISPLAY "Name: " WHO.
            DISPLAY "Location: " WHERE