***How to run the code:
1. Open command prompt in the folder where all these files are present.
2. bison -dy yacc.y
3. flex lexer.l y.tab.h
4. gcc lex.yy.c y.tab.c
5. a.exe
6. Type in the input test file name you want to run.





***Features and capabilities of our code:

1.  Can perform all the basic & advanced arithmetic operations and can evaluate expressions (Eg: x*y+z/w).
2.  Can perform boolean operations and assignment operation (Eg: x&y|z, x>5, y<=z+t, x= 5).
3.  Has int, float datatypes and can be declared using int , double respectively (double/int x ...).
    If nothing is mentioned it is taken as int (i.e. x = 5, here x is considered as integer).
4.  Can take multiple inputs from the user using cin (Eg: cin x, y, z;).
5.  Can print multiple numerical outputs using cout (Eg: cout x, y*5, z*t+l).
6.  Can print a string and an numerical output using printf (Eg: printf("Value:", x+y*z)).
7.  Can print a single numerical output using write (Eg: write x;).
8.  Can handle single line and multi-line comments ( "<<Popl" == single line , "<*Hello*>" == multi-line)
9.  Has the following control structures:
    i.    check-otherwise , nested check-otherwise(Similar to if-else in cpp).
    ii.   until (Similar to while loop in cpp). 
    iii.  loop  (Similar to for loop in cpp).
10. Can run multiple functions. The features of functions include:
    i.    Can take arguments (if it has parameters) metioned from the calling function.
    ii.   Execute all the operations in its body (mentioned in points 1 to 9).
    iii.  Can return a value using return statement, to the calling function.
    iv.   Recursive functions work too.
11. Can have multiple classes. Features of classes include:
    i.    Can have member variables.
    ii.   Can have member methods/functions which work smilar to normal functions mentioned above.
    iii.  Each class can have multiple objects created.
    iv.   Member variables can be intitialized while creating the object.
    v.    The objects created can access the member variables and member methods.
    vi.   Member methods can access member variables and change them.
    vii.  Member methods can be recursive too.