#System Software and Compilers Laboratory
#Using Lex and Yacc Libraries in Unix

lab 3,4: Command for executing curses.h as alternative for conio.h:

1. cc -w -o lab4 lab4.c -lncurses
2. ./lab4

where, -w: supress errors -o: create obj file

Programs:

1. 
   a. LEX: recognize valid arithmetic expression (+,-,*,/). Count and display each identifier and operator.
   b. YACC: evaluate arithmetic expression involving operators: +, -, *, /
   
2. YACC: recognize all strings ending with b preceded by n a’s using the grammar a^n b (note: input n value)
   
3. YACC:construct Predictive / LL(1) Parsing Table for the grammar rules: A ®aBa , B ®bB | e. Use this table to parse the sentence: abba$
   
4. YACC: demonstrate Shift Reduce Parsing technique for the grammar rules: E ®E+T | T, T ®T*F | F, F ®(E) | id and parse the sentence: id + id * id.
   
5. Design, develop and implement a C/Java program to generate the machine code using Triples for the statement A = -B * (C +D) whose intermediate code in three-address form: T1 = -B T2 = C + D T3 = T1 + T2 A = T3
   
6. 
   a. Write a LEX program to eliminate comment lines in a C program and copy the resulting program into a separate file. b. Write YACC program to recognize valid identifier, operators and keywords in the given text (C program) file.
   
7. Design, develop and implement a C/C++/Java program to simulate the working of Shortest remaining time and Round Robin (RR) scheduling algorithms. Experiment with different quantum sizes for RR algorithm.
   
8. Design, develop and implement a C/C++/Java program to implement Banker’s algorithm. Assume suitable input required to demonstrate the results.
   
9. Design, develop and implement a C/C++/Java program to implement page replacement algorithms LRU and FIFO. Assume suitable input required to demonstrate the results.