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This test is run by .
Note that your final mark will not be saved in the system.

7 - Context-free Languages Categorise

Target Level

Running Total

Attempt

1 of 3

Click on an item, then click on a category to place it. Or, drag and drop the item into the correct category. Organise all items before clicking 'Check'.

This question relates to two BNF definitions.

Definition A:

<code> ::= <textpart> | <textpart><numeral>
<textpart> ::= <letter> | <letter><textpart>
<letter> ::= a|b|c|...|z
<numeral> ::= 1|2|3|4|5|6|7|8|9

Definition B:

<value> ::= <text><digit>|<digit><text>
<text> ::= <char><char>
<char> ::= a|b|c|...|z
<digit> ::= 1|2|3

Valid according to definition A only

Valid according to definition B only

Valid according to neither definition A nor definition B

Valid according to both A and B

3aa

2bc

abc6

c2d

cd4

abcde

ab2

ab0

This is your 1^st attempt! You get 5 marks for each one you get right first time. Good luck!

Pass Mark

70%