PLC Laboratory 5 - Revision history

Beh01: /* Recursive Descent Parser */

2022-03-09T12:22:04Z

Recursive Descent Parser

2022-01-27T08:40:28Z

2022-01-27T08:37:10Z

2022-01-27T08:36:49Z

2022-01-27T08:36:08Z

2022-01-27T08:35:10Z

2022-01-27T08:33:23Z

2022-01-25T11:28:36Z

Created blank page

New page

← Older revision		Revision as of 12:22, 9 March 2022
Line 16:		Line 16:

	To simplify the solution you can use the lexical analyzer from [[PLC_Laboratory_2 \| Laboratory 2]]		To simplify the solution you can use the lexical analyzer from [[PLC_Laboratory_2 \| Laboratory 2]]
		+
		+	You can use this Scanner in [http://linedu.vsb.cz/~beh01/wiki_data/PLC_lab5_scanner.zip C#]

	== Input specification ==		== Input specification ==

← Older revision		Revision as of 08:40, 27 January 2022
Line 1:		Line 1:
−	== Recursive ~~descent parse~~ ==	+	== Recursive Descent Parser ==

	Using recursive descent, implement a parser of arithmetic expressions. These expressions contain +, -, *, / operators (with common priorities and left associativity) and parentheses. To simplify the task, consider we have only binary operators. There are no unary operators in our language. Moreover, we can use only positive integers in our expressions.		Using recursive descent, implement a parser of arithmetic expressions. These expressions contain +, -, *, / operators (with common priorities and left associativity) and parentheses. To simplify the task, consider we have only binary operators. There are no unary operators in our language. Moreover, we can use only positive integers in our expressions.

@@ Line 14: / Line 14: @@
     F  :  '(' E ')'    (9)
        |  num          (10)
 To simplify the solution you can use the lexical analyzer from [[PLC_Laboratory_2 | Laboratory 2]]

@@ Line 4: / Line 4: @@
 For the recursive descent use following grammar:
+   E  :  T E1;        (1)
 To simplify the solution you can use the lexical analyzer from [[PLC_Laboratory_2 | Laboratory 2]]

@@ Line 5: / Line 5: @@
 For the recursive descent use following grammar:
-To simplify the solution you can use the lexical analyzer from [[PLC_Laboratory_2 Laboratory 2]]
+To simplify the solution you can use the lexical analyzer from [[PLC_Laboratory_2 | Laboratory 2]]
 == Input specification ==

← Older revision		Revision as of 08:35, 27 January 2022
Line 4:		Line 4:

	For the recursive descent use following grammar:		For the recursive descent use following grammar:
		+
		+	To simplify the solution you can use the lexical analyzer from [[PLC_Laboratory_2 Laboratory 2]]

	== Input specification ==		== Input specification ==

← Older revision	Revision as of 08:33, 27 January 2022
Line 1:	Line 1:
	+	== Recursive descent parse ==

	+	Using recursive descent, implement a parser of arithmetic expressions. These expressions contain +, -, *, / operators (with common priorities and left associativity) and parentheses. To simplify the task, consider we have only binary operators. There are no unary operators in our language. Moreover, we can use only positive integers in our expressions.
	+
	+	For the recursive descent use following grammar:
	+
	+	== Input specification ==
	+
	+	The first line of the input contains a number <code>N</code>. It defines the number of expressions your program should evaluate. These expressions are on next <code>N</code> lines. Each line contains exactly one expression.
	+
	+	== Output specification ==
	+
	+	For each expression write one line containing numbers of grammar rules, that are used for parsing during the recursive descent. If there is any error in the input, write text <code>ERROR</code> instead.
	+
	+	== Example ==
	+	* Input
	+	<syntaxhighlight lang="haskell" >
	+	2
	+	2 * (3+5)
	+	15 - 2**7
	+	</syntaxhighlight >
	+
	+	* Output
	+	<syntaxhighlight lang="haskell" >
	+	1 5 10 6 9 1 5 10 8 2 5 10 8 4 8 4
	+	ERROR
	+	</syntaxhighlight >