Leetcode "202" Happy number

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, replace the number by th e sum of the squares of its digits, and repeat the process until the number equals 1 (where it would stay), or it loops end lessly in a cycle which does not include 1. Those numbers for which this process ends in 1 is happy numbers.

example:  is a happy number

• + + =
• + = -
• + + =
• + + 1

The topic is also relatively simple, the AC code is as follows:

BOOLIshappy (intN) {if(n<=0)            return false; Else if(n==1)            return true; Else        {            intsqusum=N; intlut[Ten];  for(intI=0;i<Ten; i++) Lut[i]= i*i; Vector<int>sum;  while(squsum!=1) {sum.push_back (squsum); inttmp=squsum; Squsum=0;  while(tmp>=Ten) {squsum=squsum+lut[tmp%Ten]; TMP=tmp/Ten; } squsum=squsum+Lut[tmp]; if(Squsum = =1)                    return true; Vector<int>::iterator result =Find (Sum.begin (), Sum.end (), squsum); if(Result! =sum.end ()) Break; }            return false; }    }

Note that using the lookup table, you can save a little time.

Leetcode "202" Happy number