2.4 KiB
2.4 KiB
title | id | challengeType |
---|---|---|
Iterated digits squaring | 5a23c84252665b21eecc7ec1 | 5 |
Description
15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89 7 -> 49 -> 97 -> 130 -> 10 -> 1Write a function that takes a number as a parameter and returns 1 or 89 after performing the mentioned process.
Instructions
Tests
tests:
- text: <code>iteratedSquare</code> should be a function.
testString: assert(typeof iteratedSquare=='function','<code>iteratedSquare</code> should be a function.');
- text: <code>iteratedSquare(4)</code> should return a number.
testString: assert(typeof iteratedSquare(4)=='number','<code>iteratedSquare(4)</code> should return a number.');
- text: <code>iteratedSquare(4)</code> should return <code>89</code>.
testString: assert.equal(iteratedSquare(4),89,'<code>iteratedSquare(4)</code> should return <code>89</code>.');
- text: <code>iteratedSquare(7)</code> should return <code>1</code>.
testString: assert.equal(iteratedSquare(7),1,'<code>iteratedSquare(7)</code> should return <code>1</code>.');
- text: <code>iteratedSquare(15)</code> should return <code>89</code>.
testString: assert.equal(iteratedSquare(15),89,'<code>iteratedSquare(15)</code> should return <code>89</code>.');
- text: <code>iteratedSquare(20)</code> should return <code>89</code>.
testString: assert.equal(iteratedSquare(20),89,'<code>iteratedSquare(20)</code> should return <code>89</code>.');
- text: <code>iteratedSquare(70)</code> should return <code>1</code>.
testString: assert.equal(iteratedSquare(70),1,'<code>iteratedSquare(70)</code> should return <code>1</code>.');
- text: <code>iteratedSquare(100)</code> should return <code>1</code>.
testString: assert.equal(iteratedSquare(100),1,'<code>iteratedSquare(100)</code> should return <code>1</code>.');
Challenge Seed
function iteratedSquare (n) {
// Good luck!
}
Solution
function iteratedSquare (n) {
var total;
while (n != 89 && n != 1) {
total = 0;
while (n > 0) {
total += Math.pow(n % 10, 2);
n = Math.floor(n/10);
}
n = total;
}
return n;
}