List of Happy Numbers in scala
Definition of Happy numbers taken from wikipedia.
"A happy number is defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits in base-ten, and repeat the process until the number either equals 1 (where it will stay), or it loops endlessly in a cycle that does not include 1. Those numbers for which this process ends in 1 are happy numbers, while those that do not end in 1 are unhappy numbers (or sad numbers)"
Example
19 is happy, as the associated sequence is
1*1 + 9*9 = 82,
8*8 + 2*2 = 68,
6*6 + 8*8 = 100,
1*1 + 0*0 + 0*0 = 1.
Scala code
import scala.collection.mutable.Set
object HappyNumber extends App {
def findSquareSum(n: Int): Int =
n.toString.foldLeft(0) { (product, num) => product + num.asDigit * num.asDigit }
val visited = Set[Int]()
def isHappyNumber(n: Int): Boolean = {
n match {
case 1 => true
case _ =>
if (visited contains n) false
else {
visited += n
if (isHappyNumber(findSquareSum(n))) { visited -= n; true} else false
}
}
}
(1 to 247) foreach { num => if(isHappyNumber(num)) println(num) }
}
programming-challenge interview-questions functional-programming scala mathematics
asked 10 mins ago
vikrant
335
add a comment |
Definition of Happy numbers taken from wikipedia.
"A happy number is defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits in base-ten, and repeat the process until the number either equals 1 (where it will stay), or it loops endlessly in a cycle that does not include 1. Those numbers for which this process ends in 1 are happy numbers, while those that do not end in 1 are unhappy numbers (or sad numbers)"
Example
19 is happy, as the associated sequence is
1*1 + 9*9 = 82,
8*8 + 2*2 = 68,
6*6 + 8*8 = 100,
1*1 + 0*0 + 0*0 = 1.
Scala code
import scala.collection.mutable.Set
object HappyNumber extends App {
def findSquareSum(n: Int): Int =
n.toString.foldLeft(0) { (product, num) => product + num.asDigit * num.asDigit }
val visited = Set[Int]()
def isHappyNumber(n: Int): Boolean = {
n match {
case 1 => true
case _ =>
if (visited contains n) false
else {
visited += n
if (isHappyNumber(findSquareSum(n))) { visited -= n; true} else false
}
}
}
(1 to 247) foreach { num => if(isHappyNumber(num)) println(num) }
}
programming-challenge interview-questions functional-programming scala mathematics
asked 10 mins ago
vikrant
335
add a comment |
Definition of Happy numbers taken from wikipedia.
"A happy number is defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits in base-ten, and repeat the process until the number either equals 1 (where it will stay), or it loops endlessly in a cycle that does not include 1. Those numbers for which this process ends in 1 are happy numbers, while those that do not end in 1 are unhappy numbers (or sad numbers)"
Example
19 is happy, as the associated sequence is
1*1 + 9*9 = 82,
8*8 + 2*2 = 68,
6*6 + 8*8 = 100,
1*1 + 0*0 + 0*0 = 1.
Scala code
import scala.collection.mutable.Set
object HappyNumber extends App {
def findSquareSum(n: Int): Int =
n.toString.foldLeft(0) { (product, num) => product + num.asDigit * num.asDigit }
val visited = Set[Int]()
def isHappyNumber(n: Int): Boolean = {
n match {
case 1 => true
case _ =>
if (visited contains n) false
else {
visited += n
if (isHappyNumber(findSquareSum(n))) { visited -= n; true} else false
}
}
}
(1 to 247) foreach { num => if(isHappyNumber(num)) println(num) }
}
programming-challenge interview-questions functional-programming scala mathematics
asked 10 mins ago
vikrant
335
Definition of Happy numbers taken from wikipedia.
"A happy number is defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits in base-ten, and repeat the process until the number either equals 1 (where it will stay), or it loops endlessly in a cycle that does not include 1. Those numbers for which this process ends in 1 are happy numbers, while those that do not end in 1 are unhappy numbers (or sad numbers)"
Example
19 is happy, as the associated sequence is
1*1 + 9*9 = 82,
8*8 + 2*2 = 68,
6*6 + 8*8 = 100,
1*1 + 0*0 + 0*0 = 1.
Scala code
import scala.collection.mutable.Set
object HappyNumber extends App {
def findSquareSum(n: Int): Int =
n.toString.foldLeft(0) { (product, num) => product + num.asDigit * num.asDigit }
val visited = Set[Int]()
def isHappyNumber(n: Int): Boolean = {
n match {
case 1 => true
case _ =>
if (visited contains n) false
else {
visited += n
if (isHappyNumber(findSquareSum(n))) { visited -= n; true} else false
}
}
}
(1 to 247) foreach { num => if(isHappyNumber(num)) println(num) }
}
programming-challenge interview-questions functional-programming scala mathematics
programming-challenge interview-questions functional-programming scala mathematics
asked 10 mins ago
vikrant
335
asked 10 mins ago
vikrant
335
asked 10 mins ago
vikrant
335
asked 10 mins ago
vikrant
335
asked 10 mins ago
vikrant
335
335
add a comment |
add a comment |
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