its a simple presentation on transformation of left recursion to right.

1. Transformation From
Left Recursion To
Non-Left Recursion
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2. Presented By:
Farzana Aktar
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3. Objectives
 To Eliminate Left recursion by rewriting the offending
production.
 The non-terminal A and its productions are said to be left
recursive.
 To replace left recursive by non left recursive production.
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4. What is Left Recursion? 4
 A grammar is left-recursive if and only if there exists a nonterminal
symbol that can derive to a sentential form with itself as the leftmost
symbol .
 Symbolically, where indicates the operation of making one or more
substitutions, and is any sequence of terminal and nonterminal
symbols.
 Consider a nonterminal A with two productions
A->A𝜶|β
So, the nonterminal A and its production are said to be left recursive.

5. Left Recursion’s Formula
 There is a formal technique for eliminating left-recursion from
productions . It’s a direct left recursion.
 Each rule which contains a left-recursive option
A --> Aα|β
 Introduce a new nonterminal A' and rewrite the rule as
A --> βA'
A' --> αA' | ε
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6. Working Procedure
 For implementing the code we use C language
 In the code segment, we declare char type variable.
 Here we use sprintf() and strtok() function.
 If we give a non-terminal left recursive expression as an input, then the
recursive value is eliminating.
 Then a non-left recursive expression we get as an output.
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7. Code : 7

8. Output : 8

9. 9