Leetcode oj:happy Number (Joy)

Write an algorithm to determine if a number is "happy".

A happy number is a number defined by the following process:starting with any positive integer and replace the number by the Sum of the squares of its digits, and repeat the process until the number equals 1 (where it would stay), or it loops Endl essly in a cycle which does not include 1. Those numbers for which this process ends in 1 is happy numbers.

Example:19 is a happy number

• 12 + 92 = 82
• 82 + 22 = 68
• 62 + 82 = 100
• 12 + 02 + 02 = 1

The number of joys, that is, the sum of squares of bits is added to the new number, to see if the last number is 1, is the number of happy, otherwise not. Code is relatively simple, with a set to save what has been asked is not 1 of the number, once

A later calculated number can be found in set (not 1), then it must go into the dead loop. This is supposed to return false, otherwise if a result of a calculation is 1 so long returns True, the code is shown below:

1 classSolution {2  Public:3     BOOLIshappy (intN) {4         Set<int>sample;5 Sample.insert (n);6         ints =0;7          for(;;) {8              while(n! =0){9s + = (n%Ten) * (n%Ten);TenN/=Ten; One             } A             if(s = =1) -                 return true; -             Else{ the                 if(Sample.find (s)! =sample.end ()) -                     return false; - Sample.insert (s); -n =s; +s =0; -             } +         } A     } at};

Leetcode oj:happy Number (Joy)