QBASIC PROGRAM TO DISPLAY GREATEST AMONG THREE NUMBERS (SUB)

DECLARE SUB GREATEST (A, B, C)
CLS
INPUT" ENTER THREE NUMBERS"; A, B, C
CALL GREATEST (A, B, C)
END

SUB GREATEST (A, B, C)
IF A> B AND A> C THEN
PRINT"THE GREATEST NUMBER IS"; A
ELSEIF B>A AND B> C THEN
PRINT"THE GREATEST NUMBER IS"; B
ELSE
PRINT"THE GREATEST NUMBER IS";C
END IF
END SUB