Bedingungen und Schleifen mit PERFORM

IDENTIFICATION DIVISION.
PROGRAM-ID. BEDINGUNG.

DATA DIVISION.
WORKING-STORAGE SECTION.
01 PUNKTE  PIC 999 VALUE 78.
01 TAG     PIC 9   VALUE 3.
01 NOTE    PIC X(12).

PROCEDURE DIVISION.
    IF PUNKTE >= 90
        DISPLAY "sehr gut"
    ELSE IF PUNKTE >= 75
        DISPLAY "gut"
    ELSE
        DISPLAY "weiter üben"
    END-IF
    END-IF.

    IF PUNKTE > 50 AND PUNKTE < 100
        DISPLAY "zwischen 50 und 100"
    END-IF.
    IF PUNKTE < 10 OR PUNKTE = 78
        DISPLAY "kleiner 10 oder genau 78"
    END-IF.
    IF NOT PUNKTE = 0
        DISPLAY "nicht null"
    END-IF.
    IF PUNKTE IS NUMERIC
        DISPLAY "ist numerisch"
    END-IF.

    EVALUATE TAG
        WHEN 1 DISPLAY "Montag"
        WHEN 2 THRU 4 DISPLAY "Mitte der Woche"
        WHEN 6 THRU 7 DISPLAY "Wochenende"
        WHEN OTHER DISPLAY "anderer Tag"
    END-EVALUATE.

    EVALUATE TRUE
        WHEN PUNKTE >= 90 MOVE "A" TO NOTE
        WHEN PUNKTE >= 75 MOVE "B" TO NOTE
        WHEN OTHER        MOVE "C" TO NOTE
    END-EVALUATE.
    DISPLAY "Note: " NOTE.
    STOP RUN.

IDENTIFICATION DIVISION.
PROGRAM-ID. SCHLEIFEN.

DATA DIVISION.
WORKING-STORAGE SECTION.
01 I       PIC S99 VALUE 0.
01 SUMME   PIC 9(5) VALUE 0.
01 N       PIC 99 VALUE 3.

PROCEDURE DIVISION.
HAUPT.
    PERFORM 3 TIMES
        DISPLAY "Hallo"
    END-PERFORM.

    PERFORM VARYING I FROM 1 BY 1 UNTIL I > 5
        DISPLAY "I = " I
    END-PERFORM.

    MOVE 0 TO SUMME.
    PERFORM VARYING I FROM 1 BY 1 UNTIL I > 10
        ADD I TO SUMME
    END-PERFORM.
    DISPLAY "Summe 1..10: " SUMME.

    PERFORM UNTIL N = 0
        DISPLAY "Countdown " N
        SUBTRACT 1 FROM N
    END-PERFORM.

    PERFORM VARYING I FROM 10 BY -3 UNTIL I < 1
        DISPLAY "runter " I
    END-PERFORM.

    PERFORM GRUSS.
    PERFORM GRUSS 2 TIMES.
    PERFORM RECHNE THRU RECHNE-ENDE.
    STOP RUN.

GRUSS.
    DISPLAY "Gruß aus einem Absatz".

RECHNE.
    COMPUTE SUMME = SUMME * 2.
    DISPLAY "Doppelt: " SUMME.
RECHNE-ENDE.
    EXIT.

IDENTIFICATION DIVISION.
PROGRAM-ID. MUSTER.

DATA DIVISION.
WORKING-STORAGE SECTION.
01 ZAHL     PIC 9(4) VALUE 29.
01 TEILER   PIC 9(4).
01 REST     PIC 9(4).
01 QUOT     PIC 9(4).
01 IST-PRIM PIC X VALUE "J".
   88 PRIM  VALUE "J".
01 A        PIC 9(4) VALUE 48.
01 B        PIC 9(4) VALUE 18.
01 T        PIC 9(4).

PROCEDURE DIVISION.
    PERFORM VARYING TEILER FROM 2 BY 1 UNTIL TEILER * TEILER > ZAHL
        DIVIDE ZAHL BY TEILER GIVING QUOT REMAINDER REST
        IF REST = 0
            MOVE "N" TO IST-PRIM
        END-IF
    END-PERFORM.
    IF PRIM
        DISPLAY ZAHL " ist eine Primzahl"
    ELSE
        DISPLAY ZAHL " ist keine Primzahl"
    END-IF.

    PERFORM UNTIL B = 0
        DIVIDE A BY B GIVING QUOT REMAINDER REST
        MOVE B TO A
        MOVE REST TO B
    END-PERFORM.
    DISPLAY "ggT = " A.
    STOP RUN.