Objectives: abstract data type (ADT), encapsulation
Integer types are very convenient, but their limited width makes them unsuitable for some applications where precise large values are more important than speed. Develop a class VeryLargeInteger
that can handle arbitrary long integer numbers (both negative and positive) and the basic arithmetic operations (addition, subtraction, multiplication, division, and remainder).
Hint: The number could be represented as string, the sign could be represented either as boolean
or as part of the string.
Note: Implementations of addition/subtraction through repeated use of a constant increment/decrement will not be accepted. Implementations of multiplication and division that rely on
stepwise addition or subtraction will not be accepted.
/∗∗
∗ VeryLargeInteger (VLI) is a class for arbitrary precision integer computation.
∗/
public class VeryLargeInteger f
/∗∗
∗ Constructs a new VLI object from a long integer.
∗ @param init initial value
∗/
VeryLargeInteger(long init) f /∗ YOUR CODE ∗/ g
/∗∗
∗ Constructs a new VLI object from a String.
∗ @param init initial value. Note, the string represents a valid VLI, but can
∗ be prefixed with a sign (either + or -).
∗/
VeryLargeInteger(String init) f /∗ YOUR CODE ∗/ g
/∗∗
∗ Computes this+other and returns the result in a new object.
∗ @param other the left-hand side operand.
∗ @return a new VLI representing this+other
∗/
VeryLargeInteger add(VeryLargeInteger other) f /∗ YOUR CODE ∗/ g
/∗∗
∗ Computes this-other and returns the result in a new object.
∗ @param other the left-hand side operand.
∗ @return a new VLI representing this-other
∗/
VeryLargeInteger sub(VeryLargeInteger other) f /∗ YOUR CODE ∗/ g
/∗∗
∗ Computes this∗other and returns the result in a new object.
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∗ @param other the left-hand side operand.
∗ @return a new VLI representing this∗other
∗/
VeryLargeInteger mul(VeryLargeInteger other) f /∗ YOUR CODE ∗/ g
/∗∗
∗ Computes this/other and returns the result in a new object.
∗ @param other the left-hand side operand.
∗ @return a new VLI representing this/other
∗/
VeryLargeInteger div(VeryLargeInteger other) f /∗ YOUR CODE ∗/ g
/∗∗
∗ Computes this%other and returns the result in a new object.
∗ @param other the left-hand side operand.
∗ @return a new VLI representing this%other
∗/
VeryLargeInteger mod(VeryLargeInteger other) f /∗ YOUR CODE ∗/ g
/∗∗
∗ Returns the textual representation of this VLI.
∗ @result a string representing this VLI
∗/
String toString() f /∗ YOUR CODE ∗/ g
/∗ YOUR CODE ∗/
g
Turn in a zip file named blazerid hw1.zip. The file should contain an exported Eclipse project1
with the following items.
• All files needed to compile and run your solution.
• Your tests (test driver needs to be a separate file).
• A document (or text file) that describes your design decisions, your tests, any difficulties you
had. If you would like to get a graded version on paper, add a note at the top of the report
saying \paper copy requested". If you received help from somebody else in class, please give
credit to them.
Grading (50 pts max)
• (10pts) Lab (September 14).
• (10pts) Assignment report.
• (10pts) Turned in code compiles without error or warning and code is well documented
(consider using -Xlint:all and/or checkStyle).
• (10pts) Quality of test design.
• (10pts) Constructors, addition, subtraction, multiplication, and toString work correctly.
• (10pts) Division and remainder methods operations correctly.
1If you do not use Eclipse, the turned in file also needs to have a file readme.txt in its top directory that explains
how to compile and test your code.
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