The values explicitly used in the initialization are used. However, if there is at least one constructor defined in the class other than the no-argument constructor which is absent, Java will treat the new statement without any input arguments in the same way as in the case of other missing overloaded constructors. That means it will produce a compilation error. Consider the following example. Example 95: Missing no-argument constructor The following class definition does not contain the no-argument constructor but it does provide a detailed constructor. In the main() method, the program tries to an instance of this class with the new statement without any input arguments on line 7. The program cannot be compiled successfully since it cannot find the constructor that does not take any arguments. Java will not instantiate the object using the default mechanism due to the presence of a constructor (which is the detailed constructor, in this case) in the class definition. The error can be observed in Figure 1823. public class MissingConstructor { 11 private double d; 2 public MissingConstructor(double d){ 3 this.d = d; 4 } 5 public static void main(String [] args){ 16 MissingConstructor mc = new MissingConstructor(); 17 } 18 } 19 3122 Figure 183: Compilation error due to missing a constructor Calling a Constructor from Other Constructors We have mentioned that the detailed constructor is the constructor that assigns values to each data member one by one based on the input supplied to the constructor. Comparing the no-argument constructor with the detailed constructor, we can see that the operation performed by the no-argument constructor can be considered a special case of the operation performed by the detailed constructor. This special case also assigns values to every data members but with a default set of values. The same thing applies when we compare the operation of the copy constructor with the operation of the detailed constructor. The copy constructor assigns values that are fixed by the input object to every data members.

The owner (patient) may read from its own EHR. A qualified and employed doctor may read and write the EHR of a patient registered with him/her. (iv) Object: The solution to online coursework. Policy: The coursework setter has read and access. A candidate has no access until after the marks have been published. [8 marks each] 4 CST.2004.13.5 5 Computer Graphics and Image Processing (a) Explain why display devices appear to be able to reproduce (almost) all the colours of the spectrum using only red, green and blue light. [4 marks] (b) Describe an algorithm (other than thresholding) which will convert a greyscale image (8 bits per pixel) to a bi-level black and white image (1 bit per pixel), with the same number of pixels, while retaining as much detail as possible. [8 marks] (c) Explain what specular and diffuse reflection are in the real world. State and explain equations for calculating approximations to both in a computer. [8 marks] 5 [TURN OVER CST.2004.13.6 6 Compiler Construction (a) Explain the differences (illustrating each with a small program) between (i) static and dynamic binding (scoping); [4 marks] (ii) static and dynamic typing. [2 marks] (b) Java is sometimes said to be "dynamically typed" in that a variable whose type is (class) C can be assigned a value of (class) D provided that D extends C; conversely a variable of type D can be assigned a value of type C using a cast. By considering storage layouts, explain why the former assignment is always valid and the latter sometimes invalid. [4 marks] (c) A new programming language has the notion of "statically scoped exceptions" in which the program exception foo; void f() { try { void g() { raise foo; } try { g(); } except (foo) { C2 } } except (foo) { C1 } } would execute C1 rather than C2 as the former was in scope at the raise point. By analogy with statically scoped variables, or otherwise, explain how such exceptions might be implemented on a stack. [10 marks] 6 CST.2004.13.7 7 Artificial Intelligence In the following, N is a feedforward neural network architecture taking a vector x T = ( x1 x2 · · · xn ) of n inputs.

[4 marks] (f ) Consider different versions of an optimising compiler, each of which uses IEEE standard representation for all variables. Give two reasons why they might compile a floating-point program into code that, when run, produces differing results. [2 marks] 6 CST.2016.1.7 6 Numerical Methods A picnicker brings hot black coffee and cold milk in two identical insulated flasks and then mixes them for his drink. His friend claims that the drink would have ended up the same temperature if he had mixed the two at home and brought one flask. Note: The temperature of an object is the heat energy within it divided by its heat capacity. The rate of heat energy flow from a hotter to a cooler object is their temperature difference divided by their insulation resistance. When two fluids are mixed the resultant temperature is the sum of their initial temperatures weighted by their proportions. (a) Give a suitable state vector for a simple, finite-difference, time domain simulation of the drink system. [3 marks] (b) List the initial values and any other parameters that are needed for the simulation.

Consider the use of a monad for input-output. For the purposes of this question, take the IO monad as including two operations readint and writeint which respectively read integers from stdin and write integers to stdout. Give the types of these operators. [2 marks] (c) Assume MLreadint and MLwriteint are primitives with side effects for inputoutput and consider the ML expression add1 of type int: let val x = MLreadint() in MLwriteint(x+1); x end (i) Give an equivalent expression which uses the IO monad instead of side-effects, and state its type. [3 marks] (ii) Give a function run2diff which can be applied to your answer to part (c)(i). When so applied it should give a value in the IO monad which corresponds to ML code that runs add1 twice and returns the difference between the values read. [4 marks] (d) State what happens when attempting to compile and execute the following Java fragment (explaining the origin of any error messages or exceptions which might arise). Object n = new Integer(42), o = new String
efine a sort or types (in C, Java, or ML) appropriate for holding a theoretical
linguistic structure tree coming about because of your solution to part (b). Engineering Discuss the contribution and the relative value of the following aspects of the modern development environment. Illustrate with examples from your group project, or from experience you gained working for a commercial software developer, or both. In each case, would you discard this feature if your employer let you, or insist on retaining it (even covertly) should your employer not value it? Explain your reasons. (a) Dividing a project into short development episodes or sprints. (b) Project progress visualisation tools such as PERT and GANTT charts. (c) Automated regression testing tools. (d) Source code management tools.

What problems could arise here, and how could they be overcome? [6 marks] 6 Numerical Analysis I (a) For Single Precision in the IEEE binary floating-point standard the precision is defined as 24, and the exponent requires 8 bits of storage. With reference to IEEE Single Precision, explain the terms exponent, significand, precision, sign bit, normalised number, denormal number. [6 marks] (b) Explain the term hidden bit. What are the values of the hidden bit for normalised and denormal numbers? How is the exponent stored and why? How are the exponent, significand and sign bit arranged in memory? [4 marks] (c) Let x ∗ denote the floating-point representation of a number x. Define the terms absolute error (εx) and relative error (δx) in representing x. How are εx and δx related? Define machine epsilon (εm). [3 marks] (d) Assume δx = δy = δz = εm. Using worst-case analysis, estimate δxy, εxy. Find an expression for δw where w = z − xy. [4 marks] (e) Working to 4 significant decimal digits only, compute w ∗ when x ∗ = 12, y ∗ = 12, z∗ = 14.8. Given εm ' 0 , how many significant decimal digits of w ∗ can be relied on?  on of a Turing machine that is specified by a quintuplet description. [4 marks] (c) Define the configuration of a Turing machine at step t, and establish equations that specify the configuration of a k-symbol Turing machine at step (t + 1) in terms of the configuration at the previous step t. [6 marks] (d) Explain how you would use your equations to simulate a specific Turing machine by a register machine whose program encodes the quintuplet description. To what extent does this support Turing's Thesis? [Explicit program for a register machine is not required.] [8 marks] 8 Computer Graphics and Image Processing Describe an algorithm for performing scan conversion of a set of 3D polygons, including details of clipping, projection, and the underlying 2D polygon scan conversion algorithm. You may assume that you are given the colour of each polygon and that no lighting calculations are required. Please state any additional assumptions that you need to make. Ray tracing is not an acceptable answer to this question. [20 marks] 5 Introduction to Security (a) Explain briefly mechanisms that software on a desktop computer can use to securely generate secret keys for use in cryptographic protocols. [5 marks] (b) Give two different ways of implementing residual information protection in an operating system and explain the threat addressed by each. [5 marks] (c) Consider the standard POSIX file-system access control mechanism: (i) Under which conditions can files and subdirectories be removed from a parent directory? [2 marks] (ii) Many Unix variants implement an extension known as the "sticky bit". What is its function? [2 marks] (iii) On a POSIX system that lacks support for the "sticky bit", how could you achieve an equivalent effect? [2 marks] (d) VerySafe Ltd offer two vaults with electronic locks. They open only after the correct decimal code has been entered.

Note: Complex numbers are added, subtracted, 123 and multiplied by formally applying the associative, commutative and distributive laws of algebra, together with the equation j12 = −11. Therefore, ( )( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) a jb c jd ac bd j bc ad a jb c jd a c j b d a jb c jd a c j b d  . The reciprocal or multiplicative inverse of a complex number can be written as:  2 2 2 2 1 ( ) a b b j a b a a jb , when the complex number is non-zero. Division between two complex numbers is defined as: 1 ( )( ) ( ) ( )       a jb c jd c jd a jb . Complex conjugate of a complex number a+jb is a-jb, while the magnitude of a+jb is calculated by ) 2 2 (a  b . Here is an example of the class definition for Complex, a class we use for representing complex numbers.
The two instance variables red and blue refer to the wrestlers involved in this match. The instance variable maxStat determines the maximum value that str, tou, sta, spd, lck, cou, and skl of each wrestler can be summed to. If a wrestler has such a sum exceeding maxStat, that wrestler is disqualified for the match. The instance variable rule is a FightingRule object adopted by the match. a constructor that takes an int value and a reference to a FightingRule object. It set maxStat to that int value and set rule to the FightingRule object. a method public boolean isQualified(Wrestler w) that returns true if w is qualified for the current match. Otherwise, it returns false. a method public boolean setWrestlers(Wrestler w1,Wrestler w2) that assigns the wrestler referred to by w1 to red and the wrestler referred to by w2 to blue. The method must return false if one of the wrestlers are disqualified. Otherwise, it returns true. a method public Wrestler commence() that simulates the current wrestling match based on the Give a brief and rudimentary clarification of the standards of how the language coming about because of part (b) may be utilized to a sentence structure analyser taking a token stream as information (by means of calls to work lex()) and giving as result an
theoretical language structure tree relating to.