Displaying two words in ASCII order.
000100 IDENTIFICATION DIVISION.
000200 PROGRAM-ID. WRDSRT01.
000300*----------------------------------------------
000400* Accepts 2 words from the user and then displays
000500* them in ASCII order.
000600*----------------------------------------------
000700 ENVIRONMENT DIVISION.
000800 DATA DIVISION.
000900 WORKING-STORAGE SECTION.
001000
001100 01 WORD-1 PIC X(50).
001200 01 WORD-2 PIC X(50).
001300
001400 PROCEDURE DIVISION.
001500 PROGRAM-BEGIN.
001600
001700 PERFORM INITIALIZE-PROGRAM.
001800 PERFORM ENTER-THE-WORDS.
001900 PERFORM DISPLAY-THE-WORDS.
002000
002100 PROGRAM-DONE.
002200 STOP RUN.
002300
002400* Level 2 Routines
002500
002600 INITIALIZE-PROGRAM.
002700 MOVE " " TO WORD-1.
002800 MOVE " " TO WORD-2.
002900
003000 ENTER-THE-WORDS.
003100 DISPLAY "This program will accept 2 words,".
003200 DISPLAY "and then display them".
003300 DISPLAY "in ASCII order.".
003400
003500 DISPLAY "Please enter the first word.".
003600 ACCEPT WORD-1.
003700
003800 DISPLAY "Please enter the second word.".
003900 ACCEPT WORD-2.
004000
004100 DISPLAY-THE-WORDS.
004200
004300 DISPLAY "The words in ASCII order are:".
004400
004500 IF WORD-1 > WORD-2
004600 DISPLAY WORD-2
004700 DISPLAY WORD-1.
004800
004900 IF WORD-1 NOT > WORD-2
005000 DISPLAY WORD-1
005100 DISPLAY WORD-2.
005200
Here is the sample output of wrdsrt01.cbl when the words entered are beta and alpha:
OUTPUT:
This program will accept 2 words,
and then display them
in ASCII order.
Please enter the first word.
beta
Please enter the second word.
alpha
The words in ASCII order are:
alpha
beta
ANALYSIS: Multiple statements are executed within the IF tests at lines 004500 and 004900. There are two DISPLAY statements under each of the IF tests. If WORD-1 is greater than WORD-2, or if WORD-1 occurs after WORD-2 in the ASCII sorting sequence, WORD-2 is displayed first.
You should edit, compile, and run wrdsrt01.cbl; then try it with various pairs of "words," such as ABC and abc, (space)ABC and ABC, or ABCD and ABC, to see how these are arranged in ASCII order.
Please note that many people, including experienced programmers, assume that the opposite of GREATER THAN is LESS THAN. However, testing for only these two conditions misses the case where the two entered words are identical. The complement of GREATER THAN is LESS THAN OR EQUAL which is correctly stated as NOT GREATER THAN.
You also can try a version of wrdsrt01.cbl that reverses the test in DISPLAY-THE-WORDS, as in Listing 4.6, which is just a listing of the DISPLAY-THE-WORDS paragraph. Try coding this one as wrdsrt02.cbl and satisfy yourself that the results are identical. Note that the test and display order are reversed.
