NOTE: You should do this homework on your own, not with the help of others in the class or outside the class. You may ask for clarification of questions from the TA or instructor.

PURPOSE: The purpose of this homework is to examine some of the issues and concepts related to data types, type equivalence, type inference, and memory layout and access for types.

• Do Exercise 7.9 in your textbook, page 422.

• Do Exercise 7.18 in your textbook, page 423.

• Consider the following set of type and variable declarations. The syntax for a variable declaration is typename : variable namelist; The syntax for a type declaration is type typedef : typename;

  type int[1:10] : vector;
  type vector[1:10] : matrix;
  type int[1:10[1:10] : mm;
  type vector[1:10] : zz;
  type record
    { string : lastname;
      int : phonenum;
      int : gradyear;
      int[1:10] : coursenums;
     } : studenttype;
  type record
     {
      string : firstname;
      int : age;
      int : gradyear;
      vector : coursenums;
     } : newstudenttype;
      
  type pointer to studenttype : spointer;
  pointer to studenttype : p, q;
  spointer : t,u;
  studenttype : s,r;
  newstudenttype : m,n;
  mm : c,d;
  zz : a,b;
  vector : v1, v2;
  matrix : m1, m2;
  
  (a) If we use structural equivalence for all type comparisons, which of these
  variables will be of the same types?  Justify your answer.
  
  (b) If we use strict name equivalence for all type comparisons, which
  of these variables will be of the same types?  Justify your answer.
  
  (c) If we use loose name equivalence for all type comparisons, which of
  these variables will be of the same types? Justify your answer. 
  
   Section 7.4.3 shows code for loading the value of
  A[i,j,k] when A is allocated contiguously in memory (page 376),
  and then again when A is defined using row pointers (page 378).
  For each of these cases, show the extended code segment that would
  be required to access A[i,j,k] if subscript bounds checking were required.