Modifying a constant by editing and recompiling

000100 IDENTIFICATION DIVISION.
000200 PROGRAM-ID. HELLO.
000300 ENVIRONMENT DIVISION.
000400 DATA DIVISION.
000500 PROCEDURE DIVISION.
000600
000700 PROGRAM-BEGIN.
000800 DISPLAY "I said, Hello world".
000900
001000 PROGRAM-DONE.
001100 STOP RUN.
If you want to display both messages, you have to use code however, this merely uses two different constants in one program.