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| ä |
Terminals:
end-of-input, epsilon, number, +, *, (, ), ;
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ä |
end-of-input
represents end of file
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ä |
epsilon
is an empty string needed to match an expression, it is
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not
a token, it represents the absence of a token
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ä |
+, *
are the legal operators in this language
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Non-terminal
symbols:
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statements
-> end-of-input | expression; statements
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expression
-> term expression’
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expression’
-> + term expression’ | epsilon
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term
-> factor term’
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term’
-> * factor term’ | epsilon
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factor
-> number | (expression)
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Consider
a parse tree of “1+2;”
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statements
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expression ; statements
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term expression’ end-of-input
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factor term’ + term expression’
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1 epsilon
factor term’ epsilon
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2 epsilon
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