// Lab 1: Exercise n.m
// Student number: 0123456
Use the ''assert'' keyword to present your answer. Thus if you think that the answer to Exercise 1 part (a) is ''true'' you would write the code as:
def x = 12
def y = 2
assert (x + 3 <= y * 10) == true
In general, you should present your answers using an //assertion// of the form ''assert (''//expression to be evaluated//'') =='' //your answer//. Load the script into //groovyConsole// and run it. If your assertion is true, the code will execute without error. If your answer is wrong you'll get an exception which will give you a clue about what the answer should be.
==== Exercise 1.1 ====
Use the rules of [[at-m42:summary_of_operator_precedence_rules|precedence and associativity]] to evaluate the following:
def x = 12 def y = 2 x + 3 <= y * 10
def x = 12 x = 20 y = 2 x + 3 <= y * 10
def x = 7 y = 1 x +3 != y * 10
x = 17 y = 2 x + 3 == y * 10
x = 100 y = 5 x + 3 > y * 10
"client" + "server""10" + "66""1" + "0""AT-M42".length()"".length()
def str = "Client server"
Then evaluate each of the following expressions:
str.indexOf("ie")str.indexOf("Ie")str.lastIndexOf("e")str.lastIndexOf("er")
def str = "Groovy, Groovy, Groovy"
Then evaluate the following expressions:
str.length()str.indexOf("o")str.lastIndexOf("o")str.indexOf("o", 5)str.lastIndexOf("o", 5)str.indexOf("ov", str.length() - 10)str.lastIndexOf("ov", str.length() - 4)str.lastIndexOf("o", str.indexOf("ro")
def str = "Groovy programming"
Then evaluate the following expressions:
str.length()str.substring(7, 14)str.substring(1, str.length() - 1)str.endsWith("ming")'Groovy' =~ /Groovy/'Groovy' =~ /oo/'Groovy' ==~ /Groovy/'Groovy' ==~ /oo/'Groovy' =~ /^G/'Groovy' =~ /G$/'Groovy' =~ /Gro*vy/'Groovy' =~ /Gro{2}vy/
def primes = [2, 3, 5, 7, 11, 13]
Write some suitable assertions to determine:
primes[0]primes[primes.size() - 1]primes[primes.size().intdiv(2)]primes[3..5]primes[5..<3]primes + [17]primes << [19]primes.reverse().sort()
def school = ['Electrical and Electronic Engineering' : ['EEE' : 60, 'ECS' : 10, 'ICCT' : 20],
'Mechanical Engineering' : ['Mechanical' : 100, 'Product Design': 30],
'Materials Engineering' : ['Materials' : 35]
]
Write some suitable assertions to determine:
def staffNumber = 123
def staffSalary = 458.78
prepare a formatted output statement to produce the following output:
STAFF PAY
123 456.78
Note how the numerical values are directly aligned with the text.
==== Exercise 3.2 ====
Use the ''Console'' class to develop a program that reads a measure for the number of yards, feet and inches in an imperial measurement and returns the result in metres. Note there are 3 feet in a yard, 12 inches in a foot and one inch is 2.54 cm.
==== Exercise 3.3 ====
use the ''Console'' class to develop a program that calculates the perimeter and area of a rectangle given its length and breadth.
==== Exercise 3.4 ====
Extend the definition of an item for the ''Map'' implementation of a simple adventure game such that some items have a weight and value. Test your implementation by providing suitable assertions that test the addition of a //Magic amulet// with weight 10 and value 100 to ''Jenny'''s list of carried items, and the later retrieval of these properties.
===== Part 4: Methods =====
These exercises support the first part of [[at-m42:lecture5#Methods|Lecture 5]].
==== Exercise 4.1 ====
Prepare and test a method entitled ''square'' that returns the square of its single parameter.
==== Exercise 4.2 ====
Pre-decimal UK coinage had 12 pence in a shilling and 20 shillings in a pound. Write and test methods to add and subtract two of these monetary amounts. Both methods will require 6 parameters. The first three parameters will be pounds, shilling, pence for the first amount. The second will be pounds, shilling, pence for the second amount. The result should be returned in pence.
==== Exercise 4.3 ====
Ammend exercise 4.2 to take the parameters in two lists like ''[pounds, shilling, pence]''.
==== Exercise 4.4 ====
//Challenge//: Amend exercise 4.3 to also return the result as a list ''[pounds, shilling, pence]''.
==== Exercise 4.5 ====
//Challenging//: The greatest common divisor of two integers can be determined from Euclid's algorithm. It is defined [[wp>Recursion_(computer_science)|recursively]] as:
gcd(n, m) = n if n == m
gcd(n, m) = gcd(n, m - n) if n < m
gcd(n, m) = gcd(n - m, m) otherwise
Implement a method to realize ''gcd'' and verify that ''gcd(18, 27)'' is 9
===== Part 5: Flow of Control =====
These exercises support the second part of [[at-m42:lecture5#Flow of Control|Lecture 5]].
==== Exercise 5.1 ====
Write a program that reads a single positive integer data value and then displays each individual value as a word. For example the input 932 should display
932: nine three two
==== Exercise 5.2 ====
The Groovy language does not support the ''do-while'' statement:
do {
// statements
} while (condition)
Write a code that implements this structure.
===== Part 6: Closures =====
These exercises support the first part of [[at-m42:lecture6#closures|Lecture 6]].
==== Exercise 6.1 ====
A software house is contracted to develop Groovy, Java and C# projects. Each project has one or more programmers involved, with perhaps the same individual associated with more than one project. For example, the following shows Chris, Renate and Paul involved with the Groovy project:
def softwareHouse = ['Groovy' : ['Chris', 'Renate', 'Paul'],
'Java' : ['Chris', 'Paul'],
'C#' ; ['Javier']
]
Predict the output of each of the following (verify by testing the code):
softwareHouse.each {key, value -> if (value.size() >= 2) println "${value}"
softwareHouse['Groovy'].each { g ->
softwareHouse['Java'].each { j ->
if (g == j) println "${g}"
}
}