Iteration - Java Concepts - page 386

2

1
n

2

(

ǃ x i ɨ ǃ ) x i

s =

n ɨ 1

You can compute this quantity by keeping track of the count, the sum, and
the sum of squares in the DataSet class as you process the input values.

΢΢ Exercise P6.6. Factoring of integers. Write a program that asks the user
for an integer and then prints out all its factors in increasing order. For
example, when the user enters 150, the program should print

2
3
5
5

Use a class FactorGenerator with a constructor
FactorGenerator(int numberToFactor) and methods
nextFactor and hasMoreFactors . Supply a class
FactorPrinter whose main method reads a user input, constructs a
FactorGenerator object, and prints the factors.

΢΢ Exercise P6.7. Prime numbers. Write a program that prompts the user for
an integer and then prints out all prime numbers up to that integer. For
example, when the user enters 20, the program should print

2
3
5
7
11
13
17
19

Recall that a number is a prime number if it is not divisible by any number
except 1 and itself.

Supply a class PrimeGenerator with a method nextPrime .

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