curriculum/challenges/english/blocks/rosetta-code-challenges/594810f028c0303b75339ad1.md
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, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which 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.
Implement a function that returns true if the number is happy, or false if not.
happy should be a function.
assert(typeof happy === 'function');
happy(1) should return a boolean.
assert(typeof happy(1) === 'boolean');
happy(1) should return true.
assert(happy(1));
happy(2) should return false.
assert(!happy(2));
happy(7) should return true.
assert(happy(7));
happy(10) should return true.
assert(happy(10));
happy(13) should return true.
assert(happy(13));
happy(19) should return true.
assert(happy(19));
happy(23) should return true.
assert(happy(23));
happy(28) should return true.
assert(happy(28));
happy(31) should return true.
assert(happy(31));
happy(32) should return true.
assert(happy(32));
happy(33) should return false.
assert(!happy(33));
function happy(number) {
}
function happy (number) {
let m;
let digit;
const cycle = [];
while (number !== 1 && cycle[number] !== true) {
cycle[number] = true;
m = 0;
while (number > 0) {
digit = number % 10;
m += Math.pow(digit, 2);
number = (number - digit) / 10;
}
number = m;
}
return (number === 1);
}