Leetcode 202. Happy number

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202. Happy Numbermy SubmissionsQuestionTotal accepted:56706 Total submissions:158441 difficulty:easy

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

Credits:
Special thanks to @mithmatt and @ts for adding the problem and creating all test cases.

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1 classSolution {2  Public:3     BOOLIshappy (intN) {4         if(N <0)return false;5map<int,int>MP;6          while(n! =1){7             if(Mp[n] = =1)return false;8Mp[n] =1;9n =calculate (n);Ten         } One         return true; A     } -     intCalculateintN) -     { the         intRET =0; -         inttemp =0; -          while(n) { -TEMP = n%Ten; +RET + = (temp *temp); -N/=Ten; +         } A         returnret; at     } -};

Leetcode 202. Happy number