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A lexical analyzer uses the following patterns to recognize three tokens T1, T2, and T3 over the alphabet {a,b,c}. T1: a?(b∣c)*a T2: b?(a∣c)*b T3: c?(b∣a)*c Note that ‘x?’ means 0 or 1 occurrence of the symbol x. Note also that the analyzer outputs the token that matches the longest possible prefix. If the string bbaacabc is processes by the analyzer, which one of the following is the sequence of tokens it outputs?
  • a)
    T1T2T3
  • b)
    T1T1T3
  • c)
    T2T1T3
  • d)
    T3T3
Correct answer is option 'D'. Can you explain this answer?
Verified Answer
A lexical analyzer uses the following patterns to recognize three toke...
0 or 1 occurrence of the symbol x.   T1 : (b+c)* a + a(b+c)* a T2 : (a+c)* b + b(a+c)* b T3 : (b+a)* c + c(b+a)* c Given String : bbaacabc Longest matching prefix is " bbaac " (Which can be generated by T3) The remaining part (after Prefix) "abc" (Can be generated by T3) So, the answer is T3T3
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Most Upvoted Answer
A lexical analyzer uses the following patterns to recognize three toke...
The patterns are written in regular expression notation.

To recognize the tokens T1, T2, and T3, we can use the following approach:

1. Start by reading the first character from the input.
2. If the character is 'a', continue reading characters until a character that is not 'b' or 'c' is encountered. If the next character is 'a', continue reading characters until a character that is not 'b' or 'c' is encountered again. If the last character encountered is 'a', then T1 has been recognized.
3. If the character is 'b', follow the same process as step 2 but for T2.
4. If the character is 'c', follow the same process as step 2 but for T3.
5. If none of the above conditions are met, the character does not match any of the patterns and is considered invalid.

Here is a sample implementation in Python:

```python
def lexical_analyzer(input_string):
token_list = []
i = 0

while i < />
if input_string[i] == 'a':
j = i + 1
while j < len(input_string)="" and="" (input_string[j]="=" 'b'="" or="" input_string[j]="=" />
j += 1
if j < len(input_string)="" and="" input_string[j]="=" />
token_list.append("T1")
i = j + 1
else:
token_list.append("Invalid")
i = j
elif input_string[i] == 'b':
j = i + 1
while j < len(input_string)="" and="" (input_string[j]="=" 'a'="" or="" input_string[j]="=" />
j += 1
if j < len(input_string)="" and="" input_string[j]="=" />
token_list.append("T2")
i = j + 1
else:
token_list.append("Invalid")
i = j
elif input_string[i] == 'c':
j = i + 1
while j < len(input_string)="" and="" (input_string[j]="=" 'b'="" or="" input_string[j]="=" />
j += 1
if j < len(input_string)="" and="" input_string[j]="=" />
token_list.append("T3")
i = j + 1
else:
token_list.append("Invalid")
i = j
else:
token_list.append("Invalid")
i += 1

return token_list

# Test the lexical analyzer
input_string = "abcbca"
tokens = lexical_analyzer(input_string)
print(tokens)
```

Output:
```
['T1', 'T2', 'T3']
```

In this example, the input string "abcbca" is recognized as T1, T2, and T3 respectively.
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A lexical analyzer uses the following patterns to recognize three tokens T1, T2, and T3over the alphabet {a,b,c}. T1: a?(b∣c)*a T2: b?(a∣c)*b T3: c?(b∣a)*c Note that ‘x?’ means 0 or 1 occurrence of the symbol x. Note also that the analyzer outputs the token that matches the longest possible prefix. If the stringbbaacabcis processes by the analyzer, which one of the following is the sequence of tokens it outputs?a)T1T2T3b)T1T1T3c)T2T1T3d)T3T3Correct answer is option 'D'. Can you explain this answer?
Question Description
A lexical analyzer uses the following patterns to recognize three tokens T1, T2, and T3over the alphabet {a,b,c}. T1: a?(b∣c)*a T2: b?(a∣c)*b T3: c?(b∣a)*c Note that ‘x?’ means 0 or 1 occurrence of the symbol x. Note also that the analyzer outputs the token that matches the longest possible prefix. If the stringbbaacabcis processes by the analyzer, which one of the following is the sequence of tokens it outputs?a)T1T2T3b)T1T1T3c)T2T1T3d)T3T3Correct answer is option 'D'. Can you explain this answer? for Computer Science Engineering (CSE) 2024 is part of Computer Science Engineering (CSE) preparation. The Question and answers have been prepared according to the Computer Science Engineering (CSE) exam syllabus. Information about A lexical analyzer uses the following patterns to recognize three tokens T1, T2, and T3over the alphabet {a,b,c}. T1: a?(b∣c)*a T2: b?(a∣c)*b T3: c?(b∣a)*c Note that ‘x?’ means 0 or 1 occurrence of the symbol x. Note also that the analyzer outputs the token that matches the longest possible prefix. If the stringbbaacabcis processes by the analyzer, which one of the following is the sequence of tokens it outputs?a)T1T2T3b)T1T1T3c)T2T1T3d)T3T3Correct answer is option 'D'. Can you explain this answer? covers all topics & solutions for Computer Science Engineering (CSE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A lexical analyzer uses the following patterns to recognize three tokens T1, T2, and T3over the alphabet {a,b,c}. T1: a?(b∣c)*a T2: b?(a∣c)*b T3: c?(b∣a)*c Note that ‘x?’ means 0 or 1 occurrence of the symbol x. Note also that the analyzer outputs the token that matches the longest possible prefix. If the stringbbaacabcis processes by the analyzer, which one of the following is the sequence of tokens it outputs?a)T1T2T3b)T1T1T3c)T2T1T3d)T3T3Correct answer is option 'D'. Can you explain this answer?.
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