palindrome

README

Palindrome Products

Detect palindrome products in a given range.

A palindromic number is a number that remains the same when its digits are reversed. For example, 121 is a palindromic number but 112 is not.

Given the definition of a palindromic number, we define a palindrome product to be the product c, such that a * b = c, where c is a palindromic number and a and b are integers (possibly, but not necessarily palindromic numbers).

For example, the palindromic number 9009 can be written as the palindrome product: 91 * 99 = 9009.

It's possible (and indeed common) for a palindrome product to be the product of multiple combinations of numbers. For example, the palindrome product 9 has the factors (1, 9), (3, 3), and (9, 1).

Write a program that given a range of integers, returns the smallest and largest palindromic product within that range, along with all of it's factors.

Example 1

Given the range [1, 9] (both inclusive)...

The smallest product is 1. It's factors are (1, 1). The largest product is 9. It's factors are (1, 9), (3, 3), and (9, 1).

Example 2

Given the range [10, 99] (both inclusive)...

The smallest palindrome product is 121. It's factors are (11, 11). The largest palindrome product is 9009. It's factors are (91, 99) and (99, 91).

Running the tests

To run the tests run the command go test from within the exercise directory.

If the test suite contains benchmarks, you can run these with the -bench flag:

go test -bench .

Keep in mind that each reviewer will run benchmarks on a different machine, with different specs, so the results from these benchmark tests may vary.

Further information

For more detailed information about the Go track, including how to get help if you're having trouble, please visit the exercism.io Go language page.

Source

Problem 4 at Project Euler http://projecteuler.net/problem=4

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

Documentation

Index

• type Product
  • func Products(fmin, fmax int) (pmin, pmax Product, err error)

Types

type Product

type Product struct {
	Product        int
	Factorizations [][2]int
}

func Products

func Products(fmin, fmax int) (pmin, pmax Product, err error)