IIT Bombay | MS/PhD Admission Test Dec. 2024 | Question: 1

Question

Consider the following lex script

%%
a(b|cd)*b {printf("%s#",yytext); }
a(b|cd)*cd {printf("%s#",yytext); }
a+b*d {printf("%s#",yytext); }

Tokenize the given input strings using the scanner generated using the above script and answer the questions by filling in the blanks

1. What is the output string corresponding to the input

    abbbdcdabcddc 

   ? $\_\_\_\_\_\_\_$
2. What is the output string corresponding to the input

3. abbbcdacdbccd 

   ? $\_\_\_\_\_\_\_$
4. What is the first substring in the input

   abbbdcdabcddc

   that does not match any pattern? $\_\_\_\_\_\_\_$
5. What is the last substring in the input

   abbbdcdabcddc

   that does not match any pattern? 
6. Provide the sequence of substrings in the input

   abbbcdacdbccd

   that do not match any pattern. Fill in the blanks starting from the first blank by filling as many blanks as needed. $\_\_\_\_$ , $\_\_\_\_$ , $\_\_\_\_$, $\_\_\_\_$