DEV Community

Cover image for COBOL Tutorial Series: Loop statements - Session 4
Duc Nguyen Thanh
Duc Nguyen Thanh

Posted on

COBOL Tutorial Series: Loop statements - Session 4

#cobol #development #tutorial #banking

Hello, I'm Duke

In the previous 3 sessions, I have guided you on how to develop, compile, and create a simple calculation program with condition statements using COBOL.

Today, I will be giving a tutorial on loops in COBOL.

1. In-line Perform
The statements inside PERFORM will be executed until END-PERFORM is reached.

2. Perform Varying

In perform varying, a paragraph will be executed till the condition in Until phrase becomes true.

 IDENTIFICATION DIVISION. PROGRAM-ID. ProductList. DATA DIVISION. WORKING-STORAGE SECTION. 01 WS-PRODUCT-NAME PIC X(30). 01 WS-PRODUCT-PRICE PIC 9(5)V99. 01 WS-TOTAL-PRICE PIC 9(7)V99 VALUE 0. 01 WS-COUNTER PIC 9(2) VALUE 1. 01 WS-NUMBER-OF-PRODUCTS PIC 9(2) VALUE 0. PROCEDURE DIVISION. MAIN-PROCESS. DISPLAY "How many products?". ACCEPT WS-NUMBER-OF-PRODUCTS. PERFORM VARYING WS-COUNTER FROM 1 BY 1 UNTIL WS-COUNTER > WS-NUMBER-OF-PRODUCTS DISPLAY "Name of product no. " WS-COUNTER ": " ACCEPT WS-PRODUCT-NAME DISPLAY "Price of " WS-PRODUCT-NAME ": " ACCEPT WS-PRODUCT-PRICE COMPUTE WS-TOTAL-PRICE = WS-TOTAL-PRICE + WS-PRODUCT-PRICE END-PERFORM. DISPLAY "Total price: " WS-TOTAL-PRICE. STOP RUN.
Enter fullscreen mode Exit fullscreen mode
  • WS-PRODUCT-NAME: This variable is used to store the product name, with a maximum of 30 characters (PIC X(30)).
  • WS-PRODUCT-PRICE: This variable is used to store the product price in a 5-digit and 2-decimal number format (PIC 9(5)V99).
  • WS-TOTAL-PRICE: This variable stores the total price of all products, initialized with the value 0. It has a 7-digit and 2-decimal format (PIC 9(7)V99).
  • WS-COUNTER: This variable is a counter, starting from 1 and has a 2-digit format (PIC 9(2)).
  • WS-NUMBER-OF-PRODUCTS: This variable stores the number of products entered by the user, initialized with the value 0
  • PERFORM VARYING: Starts a loop. This loop will continue until WS-COUNTER is greater than WS-NUMBER-OF-PRODUCTS.
  • FROM 1 BY 1: Sets the starting value of WS-COUNTER to 1 and increments it by 1 after each iteration.

and here is the result

result

Repository here

Top comments (0)